Text file src/cmd/compile/internal/ssa/_gen/generic.rules

     1  // Copyright 2015 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // Simplifications that apply to all backend architectures. As an example, this
     6  // Go source code
     7  //
     8  // y := 0 * x
     9  //
    10  // can be translated into y := 0 without losing any information, which saves a
    11  // pointless multiplication instruction. Other .rules files in this directory
    12  // (for example AMD64.rules) contain rules specific to the architecture in the
    13  // filename. The rules here apply to every architecture.
    14  //
    15  // The code for parsing this file lives in rulegen.go; this file generates
    16  // ssa/rewritegeneric.go.
    17  
    18  // values are specified using the following format:
    19  // (op <type> [auxint] {aux} arg0 arg1 ...)
    20  // the type, aux, and auxint fields are optional
    21  // on the matching side
    22  //  - the type, aux, and auxint fields must match if they are specified.
    23  //  - the first occurrence of a variable defines that variable.  Subsequent
    24  //    uses must match (be == to) the first use.
    25  //  - v is defined to be the value matched.
    26  //  - an additional conditional can be provided after the match pattern with "&&".
    27  // on the generated side
    28  //  - the type of the top-level expression is the same as the one on the left-hand side.
    29  //  - the type of any subexpressions must be specified explicitly (or
    30  //    be specified in the op's type field).
    31  //  - auxint will be 0 if not specified.
    32  //  - aux will be nil if not specified.
    33  
    34  // blocks are specified using the following format:
    35  // (kind controlvalue succ0 succ1 ...)
    36  // controlvalue must be "nil" or a value expression
    37  // succ* fields must be variables
    38  // For now, the generated successors must be a permutation of the matched successors.
    39  
    40  // constant folding
    41  (Trunc16to8  (Const16  [c])) => (Const8   [int8(c)])
    42  (Trunc32to8  (Const32  [c])) => (Const8   [int8(c)])
    43  (Trunc32to16 (Const32  [c])) => (Const16  [int16(c)])
    44  (Trunc64to8  (Const64  [c])) => (Const8   [int8(c)])
    45  (Trunc64to16 (Const64  [c])) => (Const16  [int16(c)])
    46  (Trunc64to32 (Const64  [c])) => (Const32  [int32(c)])
    47  (Cvt64Fto32F (Const64F [c])) => (Const32F [float32(c)])
    48  (Cvt32Fto64F (Const32F [c])) => (Const64F [float64(c)])
    49  (Cvt32to32F  (Const32  [c])) => (Const32F [float32(c)])
    50  (Cvt32to64F  (Const32  [c])) => (Const64F [float64(c)])
    51  (Cvt64to32F  (Const64  [c])) => (Const32F [float32(c)])
    52  (Cvt64to64F  (Const64  [c])) => (Const64F [float64(c)])
    53  (Cvt32Fto32  (Const32F [c])) && c >= -1<<31 && c < 1<<31 => (Const32 [int32(c)])
    54  (Cvt32Fto64  (Const32F [c])) && c >= -1<<63 && c < 1<<63 => (Const64 [int64(c)])
    55  (Cvt64Fto32  (Const64F [c])) && c >= -1<<31 && c < 1<<31 => (Const32 [int32(c)])
    56  (Cvt64Fto64  (Const64F [c])) && c >= -1<<63 && c < 1<<63 => (Const64 [int64(c)])
    57  (Round32F x:(Const32F)) => x
    58  (Round64F x:(Const64F)) => x
    59  (CvtBoolToUint8 (ConstBool [false])) => (Const8 [0])
    60  (CvtBoolToUint8 (ConstBool [true])) => (Const8 [1])
    61  (BitLen64 (Const64 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len64(uint64(c)))])
    62  (BitLen32 (Const32 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len32(uint32(c)))])
    63  (BitLen16 (Const16 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len16(uint16(c)))])
    64  (BitLen8  (Const8  [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len8(uint8(c)))])
    65  (BitLen64 (Const64 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len64(uint64(c)))])
    66  (BitLen32 (Const32 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len32(uint32(c)))])
    67  (BitLen16 (Const16 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len16(uint16(c)))])
    68  (BitLen8  (Const8  [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len8(uint8(c)))])
    69  (PopCount64 (Const64 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.OnesCount64(uint64(c)))])
    70  (PopCount32 (Const32 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.OnesCount32(uint32(c)))])
    71  (PopCount16 (Const16 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.OnesCount16(uint16(c)))])
    72  (PopCount8  (Const8  [c])) && config.PtrSize == 8 => (Const64 [int64(bits.OnesCount8(uint8(c)))])
    73  (PopCount64 (Const64 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.OnesCount64(uint64(c)))])
    74  (PopCount32 (Const32 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.OnesCount32(uint32(c)))])
    75  (PopCount16 (Const16 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.OnesCount16(uint16(c)))])
    76  (PopCount8  (Const8  [c])) && config.PtrSize == 4 => (Const32 [int32(bits.OnesCount8(uint8(c)))])
    77  (Add64carry (Const64 <t> [x]) (Const64 [y]) (Const64 [c])) && c >= 0 && c <= 1 => (MakeTuple (Const64 <t> [bitsAdd64(x, y, c).sum]) (Const64 <t> [bitsAdd64(x, y, c).carry]))
    78  
    79  (Trunc16to8  (ZeroExt8to16  x)) => x
    80  (Trunc32to8  (ZeroExt8to32  x)) => x
    81  (Trunc32to16 (ZeroExt8to32  x)) => (ZeroExt8to16  x)
    82  (Trunc32to16 (ZeroExt16to32 x)) => x
    83  (Trunc64to8  (ZeroExt8to64  x)) => x
    84  (Trunc64to16 (ZeroExt8to64  x)) => (ZeroExt8to16  x)
    85  (Trunc64to16 (ZeroExt16to64 x)) => x
    86  (Trunc64to32 (ZeroExt8to64  x)) => (ZeroExt8to32  x)
    87  (Trunc64to32 (ZeroExt16to64 x)) => (ZeroExt16to32 x)
    88  (Trunc64to32 (ZeroExt32to64 x)) => x
    89  (Trunc16to8  (SignExt8to16  x)) => x
    90  (Trunc32to8  (SignExt8to32  x)) => x
    91  (Trunc32to16 (SignExt8to32  x)) => (SignExt8to16  x)
    92  (Trunc32to16 (SignExt16to32 x)) => x
    93  (Trunc64to8  (SignExt8to64  x)) => x
    94  (Trunc64to16 (SignExt8to64  x)) => (SignExt8to16  x)
    95  (Trunc64to16 (SignExt16to64 x)) => x
    96  (Trunc64to32 (SignExt8to64  x)) => (SignExt8to32  x)
    97  (Trunc64to32 (SignExt16to64 x)) => (SignExt16to32 x)
    98  (Trunc64to32 (SignExt32to64 x)) => x
    99  
   100  (ZeroExt8to16  (Const8  [c])) => (Const16 [int16( uint8(c))])
   101  (ZeroExt8to32  (Const8  [c])) => (Const32 [int32( uint8(c))])
   102  (ZeroExt8to64  (Const8  [c])) => (Const64 [int64( uint8(c))])
   103  (ZeroExt16to32 (Const16 [c])) => (Const32 [int32(uint16(c))])
   104  (ZeroExt16to64 (Const16 [c])) => (Const64 [int64(uint16(c))])
   105  (ZeroExt32to64 (Const32 [c])) => (Const64 [int64(uint32(c))])
   106  (SignExt8to16  (Const8  [c])) => (Const16 [int16(c)])
   107  (SignExt8to32  (Const8  [c])) => (Const32 [int32(c)])
   108  (SignExt8to64  (Const8  [c])) => (Const64 [int64(c)])
   109  (SignExt16to32 (Const16 [c])) => (Const32 [int32(c)])
   110  (SignExt16to64 (Const16 [c])) => (Const64 [int64(c)])
   111  (SignExt32to64 (Const32 [c])) => (Const64 [int64(c)])
   112  
   113  (Neg8   (Const8   [c])) => (Const8   [-c])
   114  (Neg16  (Const16  [c])) => (Const16  [-c])
   115  (Neg32  (Const32  [c])) => (Const32  [-c])
   116  (Neg64  (Const64  [c])) => (Const64  [-c])
   117  (Neg32F (Const32F [c])) && c != 0 => (Const32F [-c])
   118  (Neg64F (Const64F [c])) && c != 0 => (Const64F [-c])
   119  
   120  (Add8   (Const8 [c])   (Const8 [d]))   => (Const8  [c+d])
   121  (Add16  (Const16 [c])  (Const16 [d]))  => (Const16 [c+d])
   122  (Add32  (Const32 [c])  (Const32 [d]))  => (Const32 [c+d])
   123  (Add64  (Const64 [c])  (Const64 [d]))  => (Const64 [c+d])
   124  (Add32F (Const32F [c]) (Const32F [d])) && c+d == c+d => (Const32F [c+d])
   125  (Add64F (Const64F [c]) (Const64F [d])) && c+d == c+d => (Const64F [c+d])
   126  (AddPtr <t> x (Const64 [c])) => (OffPtr <t> x [c])
   127  (AddPtr <t> x (Const32 [c])) => (OffPtr <t> x [int64(c)])
   128  
   129  (Sub8   (Const8 [c]) (Const8 [d]))     => (Const8 [c-d])
   130  (Sub16  (Const16 [c]) (Const16 [d]))   => (Const16 [c-d])
   131  (Sub32  (Const32 [c]) (Const32 [d]))   => (Const32 [c-d])
   132  (Sub64  (Const64 [c]) (Const64 [d]))   => (Const64 [c-d])
   133  (Sub32F (Const32F [c]) (Const32F [d])) && c-d == c-d => (Const32F [c-d])
   134  (Sub64F (Const64F [c]) (Const64F [d])) && c-d == c-d => (Const64F [c-d])
   135  
   136  (Mul8   (Const8 [c])   (Const8 [d]))   => (Const8  [c*d])
   137  (Mul16  (Const16 [c])  (Const16 [d]))  => (Const16 [c*d])
   138  (Mul32  (Const32 [c])  (Const32 [d]))  => (Const32 [c*d])
   139  (Mul64  (Const64 [c])  (Const64 [d]))  => (Const64 [c*d])
   140  (Mul32F (Const32F [c]) (Const32F [d])) && c*d == c*d => (Const32F [c*d])
   141  (Mul64F (Const64F [c]) (Const64F [d])) && c*d == c*d => (Const64F [c*d])
   142  (Mul32uhilo (Const32 [c]) (Const32 [d])) => (MakeTuple (Const32 <typ.UInt32> [bitsMulU32(c, d).hi]) (Const32 <typ.UInt32> [bitsMulU32(c,d).lo]))
   143  (Mul64uhilo (Const64 [c]) (Const64 [d])) => (MakeTuple (Const64 <typ.UInt64> [bitsMulU64(c, d).hi]) (Const64 <typ.UInt64> [bitsMulU64(c,d).lo]))
   144  (Mul32uover (Const32 [c]) (Const32 [d])) => (MakeTuple (Const32 <typ.UInt32> [bitsMulU32(c, d).lo]) (ConstBool <typ.Bool> [bitsMulU32(c,d).hi != 0]))
   145  (Mul64uover (Const64 [c]) (Const64 [d])) => (MakeTuple (Const64 <typ.UInt64> [bitsMulU64(c, d).lo]) (ConstBool <typ.Bool> [bitsMulU64(c,d).hi != 0]))
   146  
   147  (And8   (Const8 [c])   (Const8 [d]))   => (Const8  [c&d])
   148  (And16  (Const16 [c])  (Const16 [d]))  => (Const16 [c&d])
   149  (And32  (Const32 [c])  (Const32 [d]))  => (Const32 [c&d])
   150  (And64  (Const64 [c])  (Const64 [d]))  => (Const64 [c&d])
   151  
   152  (Or8   (Const8 [c])   (Const8 [d]))   => (Const8  [c|d])
   153  (Or16  (Const16 [c])  (Const16 [d]))  => (Const16 [c|d])
   154  (Or32  (Const32 [c])  (Const32 [d]))  => (Const32 [c|d])
   155  (Or64  (Const64 [c])  (Const64 [d]))  => (Const64 [c|d])
   156  
   157  (Xor8   (Const8 [c])   (Const8 [d]))   => (Const8  [c^d])
   158  (Xor16  (Const16 [c])  (Const16 [d]))  => (Const16 [c^d])
   159  (Xor32  (Const32 [c])  (Const32 [d]))  => (Const32 [c^d])
   160  (Xor64  (Const64 [c])  (Const64 [d]))  => (Const64 [c^d])
   161  
   162  (Ctz64 (Const64 [c])) && config.PtrSize == 4 => (Const32 [int32(ntz64(c))])
   163  (Ctz32 (Const32 [c])) && config.PtrSize == 4 => (Const32 [int32(ntz32(c))])
   164  (Ctz16 (Const16 [c])) && config.PtrSize == 4 => (Const32 [int32(ntz16(c))])
   165  (Ctz8  (Const8  [c])) && config.PtrSize == 4 => (Const32 [int32(ntz8(c))])
   166  
   167  (Ctz64 (Const64 [c])) && config.PtrSize == 8 => (Const64 [int64(ntz64(c))])
   168  (Ctz32 (Const32 [c])) && config.PtrSize == 8 => (Const64 [int64(ntz32(c))])
   169  (Ctz16 (Const16 [c])) && config.PtrSize == 8 => (Const64 [int64(ntz16(c))])
   170  (Ctz8  (Const8  [c])) && config.PtrSize == 8 => (Const64 [int64(ntz8(c))])
   171  
   172  (Div8   (Const8  [c])  (Const8  [d])) && d != 0 => (Const8  [c/d])
   173  (Div16  (Const16 [c])  (Const16 [d])) && d != 0 => (Const16 [c/d])
   174  (Div32  (Const32 [c])  (Const32 [d])) && d != 0 => (Const32 [c/d])
   175  (Div64  (Const64 [c])  (Const64 [d])) && d != 0 => (Const64 [c/d])
   176  (Div8u  (Const8  [c])  (Const8  [d])) && d != 0 => (Const8  [int8(uint8(c)/uint8(d))])
   177  (Div16u (Const16 [c])  (Const16 [d])) && d != 0 => (Const16 [int16(uint16(c)/uint16(d))])
   178  (Div32u (Const32 [c])  (Const32 [d])) && d != 0 => (Const32 [int32(uint32(c)/uint32(d))])
   179  (Div64u (Const64 [c])  (Const64 [d])) && d != 0 => (Const64 [int64(uint64(c)/uint64(d))])
   180  (Div32F (Const32F [c]) (Const32F [d])) && c/d == c/d => (Const32F [c/d])
   181  (Div64F (Const64F [c]) (Const64F [d])) && c/d == c/d => (Const64F [c/d])
   182  (Div128u <t> (Const64 [0]) lo y) => (MakeTuple (Div64u <t.FieldType(0)> lo y) (Mod64u <t.FieldType(1)> lo y))
   183  
   184  (Not (ConstBool [c])) => (ConstBool [!c])
   185  
   186  (Floor       (Const64F [c])) => (Const64F [math.Floor(c)])
   187  (Ceil        (Const64F [c])) => (Const64F [math.Ceil(c)])
   188  (Trunc       (Const64F [c])) => (Const64F [math.Trunc(c)])
   189  (RoundToEven (Const64F [c])) => (Const64F [math.RoundToEven(c)])
   190  
   191  // Convert x * 1 to x.
   192  (Mul(8|16|32|64)  (Const(8|16|32|64)  [1]) x) => x
   193  (Mul(32|64)uover <t> (Const(32|64) [1]) x) => (MakeTuple x (ConstBool <t.FieldType(1)> [false]))
   194  
   195  // Convert x * -1 to -x.
   196  (Mul(8|16|32|64)  (Const(8|16|32|64)  [-1]) x) => (Neg(8|16|32|64)  x)
   197  
   198  // Convert -x * c to x * -c
   199  (Mul(8|16|32|64) (Const(8|16|32|64) <t> [c]) (Neg(8|16|32|64) x)) => (Mul(8|16|32|64) x (Const(8|16|32|64) <t> [-c]))
   200  
   201  (Mul(8|16|32|64) (Neg(8|16|32|64) x) (Neg(8|16|32|64) y)) => (Mul(8|16|32|64) x y)
   202  
   203  // simplify negative on mul if possible
   204  (Neg(8|16|32|64) (Mul(8|16|32|64) x (Const(8|16|32|64) <t> [c]))) => (Mul(8|16|32|64) x (Const(8|16|32|64) <t> [-c]))
   205  (Neg(8|16|32|64) (Mul(8|16|32|64) x (Neg(8|16|32|64) y))) => (Mul(8|16|32|64) x y)
   206  
   207  // DeMorgan's Laws
   208  (And(8|16|32|64) <t> (Com(8|16|32|64) x) (Com(8|16|32|64) y)) => (Com(8|16|32|64) (Or(8|16|32|64) <t> x y))
   209  (Or(8|16|32|64) <t> (Com(8|16|32|64) x) (Com(8|16|32|64) y)) => (Com(8|16|32|64) (And(8|16|32|64) <t> x y))
   210  
   211  // Absorption laws
   212  (And(8|16|32|64) x (Or(8|16|32|64) x y)) => x
   213  (Or(8|16|32|64) x (And(8|16|32|64) x y)) => x
   214  
   215  (Mod8  (Const8  [c]) (Const8  [d])) && d != 0 => (Const8  [c % d])
   216  (Mod16 (Const16 [c]) (Const16 [d])) && d != 0 => (Const16 [c % d])
   217  (Mod32 (Const32 [c]) (Const32 [d])) && d != 0 => (Const32 [c % d])
   218  (Mod64 (Const64 [c]) (Const64 [d])) && d != 0 => (Const64 [c % d])
   219  
   220  (Mod8u  (Const8 [c])  (Const8  [d])) && d != 0 => (Const8  [int8(uint8(c) % uint8(d))])
   221  (Mod16u (Const16 [c]) (Const16 [d])) && d != 0 => (Const16 [int16(uint16(c) % uint16(d))])
   222  (Mod32u (Const32 [c]) (Const32 [d])) && d != 0 => (Const32 [int32(uint32(c) % uint32(d))])
   223  (Mod64u (Const64 [c]) (Const64 [d])) && d != 0 => (Const64 [int64(uint64(c) % uint64(d))])
   224  
   225  (Lsh64x64  (Const64 [c]) (Const64 [d])) => (Const64 [c << uint64(d)])
   226  (Rsh64x64  (Const64 [c]) (Const64 [d])) => (Const64 [c >> uint64(d)])
   227  (Rsh64Ux64 (Const64 [c]) (Const64 [d])) => (Const64 [int64(uint64(c) >> uint64(d))])
   228  (Lsh32x64  (Const32 [c]) (Const64 [d])) => (Const32 [c << uint64(d)])
   229  (Rsh32x64  (Const32 [c]) (Const64 [d])) => (Const32 [c >> uint64(d)])
   230  (Rsh32Ux64 (Const32 [c]) (Const64 [d])) => (Const32 [int32(uint32(c) >> uint64(d))])
   231  (Lsh16x64  (Const16 [c]) (Const64 [d])) => (Const16 [c << uint64(d)])
   232  (Rsh16x64  (Const16 [c]) (Const64 [d])) => (Const16 [c >> uint64(d)])
   233  (Rsh16Ux64 (Const16 [c]) (Const64 [d])) => (Const16 [int16(uint16(c) >> uint64(d))])
   234  (Lsh8x64   (Const8  [c]) (Const64 [d])) => (Const8  [c << uint64(d)])
   235  (Rsh8x64   (Const8  [c]) (Const64 [d])) => (Const8  [c >> uint64(d)])
   236  (Rsh8Ux64  (Const8  [c]) (Const64 [d])) => (Const8  [int8(uint8(c) >> uint64(d))])
   237  
   238  // Fold IsInBounds when the range of the index cannot exceed the limit.
   239  (IsInBounds (ZeroExt8to32  _) (Const32 [c])) && (1 << 8)  <= c => (ConstBool [true])
   240  (IsInBounds (ZeroExt8to64  _) (Const64 [c])) && (1 << 8)  <= c => (ConstBool [true])
   241  (IsInBounds (ZeroExt16to32 _) (Const32 [c])) && (1 << 16) <= c => (ConstBool [true])
   242  (IsInBounds (ZeroExt16to64 _) (Const64 [c])) && (1 << 16) <= c => (ConstBool [true])
   243  (IsInBounds x x) => (ConstBool [false])
   244  (IsInBounds                (And8  (Const8  [c]) _)  (Const8  [d])) && 0 <= c && c < d => (ConstBool [true])
   245  (IsInBounds (ZeroExt8to16  (And8  (Const8  [c]) _)) (Const16 [d])) && 0 <= c && int16(c) < d => (ConstBool [true])
   246  (IsInBounds (ZeroExt8to32  (And8  (Const8  [c]) _)) (Const32 [d])) && 0 <= c && int32(c) < d => (ConstBool [true])
   247  (IsInBounds (ZeroExt8to64  (And8  (Const8  [c]) _)) (Const64 [d])) && 0 <= c && int64(c) < d => (ConstBool [true])
   248  (IsInBounds                (And16 (Const16 [c]) _)  (Const16 [d])) && 0 <= c && c < d => (ConstBool [true])
   249  (IsInBounds (ZeroExt16to32 (And16 (Const16 [c]) _)) (Const32 [d])) && 0 <= c && int32(c) < d => (ConstBool [true])
   250  (IsInBounds (ZeroExt16to64 (And16 (Const16 [c]) _)) (Const64 [d])) && 0 <= c && int64(c) < d => (ConstBool [true])
   251  (IsInBounds                (And32 (Const32 [c]) _)  (Const32 [d])) && 0 <= c && c < d => (ConstBool [true])
   252  (IsInBounds (ZeroExt32to64 (And32 (Const32 [c]) _)) (Const64 [d])) && 0 <= c && int64(c) < d => (ConstBool [true])
   253  (IsInBounds                (And64 (Const64 [c]) _)  (Const64 [d])) && 0 <= c && c < d => (ConstBool [true])
   254  (IsInBounds (Const32 [c]) (Const32 [d])) => (ConstBool [0 <= c && c < d])
   255  (IsInBounds (Const64 [c]) (Const64 [d])) => (ConstBool [0 <= c && c < d])
   256  // (Mod64u x y) is always between 0 (inclusive) and y (exclusive).
   257  (IsInBounds (Mod32u _ y) y) => (ConstBool [true])
   258  (IsInBounds (Mod64u _ y) y) => (ConstBool [true])
   259  // Right shifting an unsigned number limits its value.
   260  (IsInBounds (ZeroExt8to64  (Rsh8Ux64  _ (Const64 [c]))) (Const64 [d])) && 0 < c && c <  8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
   261  (IsInBounds (ZeroExt8to32  (Rsh8Ux64  _ (Const64 [c]))) (Const32 [d])) && 0 < c && c <  8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
   262  (IsInBounds (ZeroExt8to16  (Rsh8Ux64  _ (Const64 [c]))) (Const16 [d])) && 0 < c && c <  8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
   263  (IsInBounds                (Rsh8Ux64  _ (Const64 [c]))  (Const64 [d])) && 0 < c && c <  8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
   264  (IsInBounds (ZeroExt16to64 (Rsh16Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d => (ConstBool [true])
   265  (IsInBounds (ZeroExt16to32 (Rsh16Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d => (ConstBool [true])
   266  (IsInBounds                (Rsh16Ux64 _ (Const64 [c]))  (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d => (ConstBool [true])
   267  (IsInBounds (ZeroExt32to64 (Rsh32Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 32 && 1<<uint(32-c)-1 < d => (ConstBool [true])
   268  (IsInBounds                (Rsh32Ux64 _ (Const64 [c]))  (Const64 [d])) && 0 < c && c < 32 && 1<<uint(32-c)-1 < d => (ConstBool [true])
   269  (IsInBounds                (Rsh64Ux64 _ (Const64 [c]))  (Const64 [d])) && 0 < c && c < 64 && 1<<uint(64-c)-1 < d => (ConstBool [true])
   270  
   271  (IsSliceInBounds x x) => (ConstBool [true])
   272  (IsSliceInBounds (And32 (Const32 [c]) _) (Const32 [d])) && 0 <= c && c <= d => (ConstBool [true])
   273  (IsSliceInBounds (And64 (Const64 [c]) _) (Const64 [d])) && 0 <= c && c <= d => (ConstBool [true])
   274  (IsSliceInBounds (Const32 [0]) _) => (ConstBool [true])
   275  (IsSliceInBounds (Const64 [0]) _) => (ConstBool [true])
   276  (IsSliceInBounds (Const32 [c]) (Const32 [d])) => (ConstBool [0 <= c && c <= d])
   277  (IsSliceInBounds (Const64 [c]) (Const64 [d])) => (ConstBool [0 <= c && c <= d])
   278  (IsSliceInBounds (SliceLen x) (SliceCap x)) => (ConstBool [true])
   279  
   280  (Eq(64|32|16|8|B) x x) => (ConstBool [true])
   281  (EqB (ConstBool [c]) (ConstBool [d])) => (ConstBool [c == d])
   282  (EqB (ConstBool [false]) x) => (Not x)
   283  (EqB (ConstBool [true]) x) => x
   284  (EqB (Not x) y) => (NeqB x y)
   285  
   286  (Neq(64|32|16|8|B) x x) => (ConstBool [false])
   287  (NeqB (ConstBool [c]) (ConstBool [d])) => (ConstBool [c != d])
   288  (NeqB (ConstBool [false]) x) => x
   289  (NeqB (ConstBool [true]) x) => (Not x)
   290  (NeqB (Not x) y) => (EqB x y)
   291  
   292  (CondSelect x _ (ConstBool [true ])) => x
   293  (CondSelect _ y (ConstBool [false])) => y
   294  (CondSelect x x _) => x
   295  
   296  // fold eq / neq between a constant and a compile time bijective operation into the constant.
   297  (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [c]) o:(Add(64|32|16|8) (Const(64|32|16|8) [d]) x)) && o.Uses == 1 => (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [c-d]) x)
   298  (Neq(64|32|16|8) (Const(64|32|16|8) <t> [c]) o:(Add(64|32|16|8) (Const(64|32|16|8) [d]) x)) && o.Uses == 1 => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [c-d]) x)
   299  
   300  (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [c]) o:(Sub(64|32|16|8) x (Const(64|32|16|8) [d]))) && o.Uses == 1 => (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [c+d]) x)
   301  (Neq(64|32|16|8) (Const(64|32|16|8) <t> [c]) o:(Sub(64|32|16|8) x (Const(64|32|16|8) [d]))) && o.Uses == 1 => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [c+d]) x)
   302  
   303  (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [c]) o:(Sub(64|32|16|8) (Const(64|32|16|8) [d]) x)) && o.Uses == 1 => (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [d-c]) x)
   304  (Neq(64|32|16|8) (Const(64|32|16|8) <t> [c]) o:(Sub(64|32|16|8) (Const(64|32|16|8) [d]) x)) && o.Uses == 1 => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [d-c]) x)
   305  
   306  (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [c]) o:(Xor(64|32|16|8) (Const(64|32|16|8) [d]) x)) && o.Uses == 1 => (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [d^c]) x)
   307  (Neq(64|32|16|8) (Const(64|32|16|8) <t> [c]) o:(Xor(64|32|16|8) (Const(64|32|16|8) [d]) x)) && o.Uses == 1 => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [d^c]) x)
   308  
   309  (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [c]) o:(Com(64|32|16|8) x)) && o.Uses == 1 => (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [^c]) x)
   310  (Neq(64|32|16|8) (Const(64|32|16|8) <t> [c]) o:(Com(64|32|16|8) x)) && o.Uses == 1 => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [^c]) x)
   311  
   312  (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [c]) o:(Neg(64|32|16|8) x)) && o.Uses == 1 => (Eq(64|32|16|8)  (Const(64|32|16|8) <t> [-c]) x)
   313  (Neq(64|32|16|8) (Const(64|32|16|8) <t> [c]) o:(Neg(64|32|16|8) x)) && o.Uses == 1 => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [-c]) x)
   314  
   315  ((Eq|Neq)64  (Const64 <t> [c]) o:(Mul64 (Const64 [d]) x)) && uint64(d)%2 == 1 && o.Uses == 1 => ((Eq|Neq)64  (Const64 <t> [int64(uint64(c) *        modularMultiplicativeInverse(uint64(d))) ]) x)
   316  ((Eq|Neq)32  (Const32 <t> [c]) o:(Mul32 (Const32 [d]) x)) && uint32(d)%2 == 1 && o.Uses == 1 => ((Eq|Neq)32  (Const32 <t> [int32(uint32(c) * uint32(modularMultiplicativeInverse(uint64(d))))]) x)
   317  ((Eq|Neq)16  (Const16 <t> [c]) o:(Mul16 (Const16 [d]) x)) && uint16(d)%2 == 1 && o.Uses == 1 => ((Eq|Neq)16  (Const16 <t> [int16(uint16(c) * uint16(modularMultiplicativeInverse(uint64(d))))]) x)
   318  ((Eq|Neq)8   (Const8  <t> [c]) o:(Mul8  (Const8  [d]) x)) && uint8( d)%2 == 1 && o.Uses == 1 => ((Eq|Neq)8   (Const8  <t> [int8( uint8( c) * uint8( modularMultiplicativeInverse(uint64(d))))]) x)
   319  
   320  // signed integer range: ( c <= x && x (<|<=) d ) -> ( unsigned(x-c) (<|<=) unsigned(d-c) )
   321  (AndB (Leq64 (Const64 [c]) x) ((Less|Leq)64 x (Const64 [d]))) && d >= c => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c])) (Const64 <x.Type> [d-c]))
   322  (AndB (Leq32 (Const32 [c]) x) ((Less|Leq)32 x (Const32 [d]))) && d >= c => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c])) (Const32 <x.Type> [d-c]))
   323  (AndB (Leq16 (Const16 [c]) x) ((Less|Leq)16 x (Const16 [d]))) && d >= c => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c])) (Const16 <x.Type> [d-c]))
   324  (AndB (Leq8  (Const8  [c]) x) ((Less|Leq)8  x (Const8  [d]))) && d >= c => ((Less|Leq)8U  (Sub8  <x.Type> x (Const8  <x.Type> [c])) (Const8  <x.Type> [d-c]))
   325  
   326  // signed integer range: ( c < x && x (<|<=) d ) -> ( unsigned(x-(c+1)) (<|<=) unsigned(d-(c+1)) )
   327  (AndB (Less64 (Const64 [c]) x) ((Less|Leq)64 x (Const64 [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c+1])) (Const64 <x.Type> [d-c-1]))
   328  (AndB (Less32 (Const32 [c]) x) ((Less|Leq)32 x (Const32 [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c+1])) (Const32 <x.Type> [d-c-1]))
   329  (AndB (Less16 (Const16 [c]) x) ((Less|Leq)16 x (Const16 [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c+1])) (Const16 <x.Type> [d-c-1]))
   330  (AndB (Less8  (Const8  [c]) x) ((Less|Leq)8  x (Const8  [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)8U  (Sub8  <x.Type> x (Const8  <x.Type> [c+1])) (Const8  <x.Type> [d-c-1]))
   331  
   332  // unsigned integer range: ( c <= x && x (<|<=) d ) -> ( x-c (<|<=) d-c )
   333  (AndB (Leq64U (Const64 [c]) x) ((Less|Leq)64U x (Const64 [d]))) && uint64(d) >= uint64(c) => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c])) (Const64 <x.Type> [d-c]))
   334  (AndB (Leq32U (Const32 [c]) x) ((Less|Leq)32U x (Const32 [d]))) && uint32(d) >= uint32(c) => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c])) (Const32 <x.Type> [d-c]))
   335  (AndB (Leq16U (Const16 [c]) x) ((Less|Leq)16U x (Const16 [d]))) && uint16(d) >= uint16(c) => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c])) (Const16 <x.Type> [d-c]))
   336  (AndB (Leq8U  (Const8  [c]) x) ((Less|Leq)8U  x (Const8  [d]))) && uint8(d)  >= uint8(c)  => ((Less|Leq)8U  (Sub8  <x.Type> x (Const8  <x.Type> [c])) (Const8  <x.Type> [d-c]))
   337  
   338  // unsigned integer range: ( c < x && x (<|<=) d ) -> ( x-(c+1) (<|<=) d-(c+1) )
   339  (AndB (Less64U (Const64 [c]) x) ((Less|Leq)64U x (Const64 [d]))) && uint64(d) >= uint64(c+1) && uint64(c+1) > uint64(c) => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c+1])) (Const64 <x.Type> [d-c-1]))
   340  (AndB (Less32U (Const32 [c]) x) ((Less|Leq)32U x (Const32 [d]))) && uint32(d) >= uint32(c+1) && uint32(c+1) > uint32(c) => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c+1])) (Const32 <x.Type> [d-c-1]))
   341  (AndB (Less16U (Const16 [c]) x) ((Less|Leq)16U x (Const16 [d]))) && uint16(d) >= uint16(c+1) && uint16(c+1) > uint16(c) => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c+1])) (Const16 <x.Type> [d-c-1]))
   342  (AndB (Less8U  (Const8  [c]) x) ((Less|Leq)8U  x (Const8  [d]))) && uint8(d)  >= uint8(c+1)  && uint8(c+1)  > uint8(c)  => ((Less|Leq)8U  (Sub8  <x.Type> x (Const8  <x.Type> [c+1]))  (Const8  <x.Type> [d-c-1]))
   343  
   344  // signed integer range: ( c (<|<=) x || x < d ) -> ( unsigned(c-d) (<|<=) unsigned(x-d) )
   345  (OrB ((Less|Leq)64 (Const64 [c]) x) (Less64 x (Const64 [d]))) && c >= d => ((Less|Leq)64U (Const64 <x.Type> [c-d]) (Sub64 <x.Type> x (Const64 <x.Type> [d])))
   346  (OrB ((Less|Leq)32 (Const32 [c]) x) (Less32 x (Const32 [d]))) && c >= d => ((Less|Leq)32U (Const32 <x.Type> [c-d]) (Sub32 <x.Type> x (Const32 <x.Type> [d])))
   347  (OrB ((Less|Leq)16 (Const16 [c]) x) (Less16 x (Const16 [d]))) && c >= d => ((Less|Leq)16U (Const16 <x.Type> [c-d]) (Sub16 <x.Type> x (Const16 <x.Type> [d])))
   348  (OrB ((Less|Leq)8  (Const8  [c]) x) (Less8  x (Const8  [d]))) && c >= d => ((Less|Leq)8U  (Const8  <x.Type> [c-d]) (Sub8  <x.Type> x (Const8  <x.Type> [d])))
   349  
   350  // signed integer range: ( c (<|<=) x || x <= d ) -> ( unsigned(c-(d+1)) (<|<=) unsigned(x-(d+1)) )
   351  (OrB ((Less|Leq)64 (Const64 [c]) x) (Leq64 x (Const64 [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)64U (Const64 <x.Type> [c-d-1]) (Sub64 <x.Type> x (Const64 <x.Type> [d+1])))
   352  (OrB ((Less|Leq)32 (Const32 [c]) x) (Leq32 x (Const32 [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)32U (Const32 <x.Type> [c-d-1]) (Sub32 <x.Type> x (Const32 <x.Type> [d+1])))
   353  (OrB ((Less|Leq)16 (Const16 [c]) x) (Leq16 x (Const16 [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)16U (Const16 <x.Type> [c-d-1]) (Sub16 <x.Type> x (Const16 <x.Type> [d+1])))
   354  (OrB ((Less|Leq)8  (Const8  [c]) x) (Leq8  x (Const8  [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)8U  (Const8  <x.Type> [c-d-1]) (Sub8  <x.Type> x (Const8  <x.Type> [d+1])))
   355  
   356  // unsigned integer range: ( c (<|<=) x || x < d ) -> ( c-d (<|<=) x-d )
   357  (OrB ((Less|Leq)64U (Const64 [c]) x) (Less64U x (Const64 [d]))) && uint64(c) >= uint64(d) => ((Less|Leq)64U (Const64 <x.Type> [c-d]) (Sub64 <x.Type> x (Const64 <x.Type> [d])))
   358  (OrB ((Less|Leq)32U (Const32 [c]) x) (Less32U x (Const32 [d]))) && uint32(c) >= uint32(d) => ((Less|Leq)32U (Const32 <x.Type> [c-d]) (Sub32 <x.Type> x (Const32 <x.Type> [d])))
   359  (OrB ((Less|Leq)16U (Const16 [c]) x) (Less16U x (Const16 [d]))) && uint16(c) >= uint16(d) => ((Less|Leq)16U (Const16 <x.Type> [c-d]) (Sub16 <x.Type> x (Const16 <x.Type> [d])))
   360  (OrB ((Less|Leq)8U  (Const8  [c]) x) (Less8U  x (Const8  [d]))) && uint8(c)  >= uint8(d)  => ((Less|Leq)8U  (Const8  <x.Type> [c-d]) (Sub8  <x.Type> x (Const8  <x.Type> [d])))
   361  
   362  // unsigned integer range: ( c (<|<=) x || x <= d ) -> ( c-(d+1) (<|<=) x-(d+1) )
   363  (OrB ((Less|Leq)64U (Const64 [c]) x) (Leq64U x (Const64 [d]))) && uint64(c) >= uint64(d+1) && uint64(d+1) > uint64(d) => ((Less|Leq)64U (Const64 <x.Type> [c-d-1]) (Sub64 <x.Type> x (Const64 <x.Type> [d+1])))
   364  (OrB ((Less|Leq)32U (Const32 [c]) x) (Leq32U x (Const32 [d]))) && uint32(c) >= uint32(d+1) && uint32(d+1) > uint32(d) => ((Less|Leq)32U (Const32 <x.Type> [c-d-1]) (Sub32 <x.Type> x (Const32 <x.Type> [d+1])))
   365  (OrB ((Less|Leq)16U (Const16 [c]) x) (Leq16U x (Const16 [d]))) && uint16(c) >= uint16(d+1) && uint16(d+1) > uint16(d) => ((Less|Leq)16U (Const16 <x.Type> [c-d-1]) (Sub16 <x.Type> x (Const16 <x.Type> [d+1])))
   366  (OrB ((Less|Leq)8U  (Const8  [c]) x) (Leq8U  x (Const8  [d]))) && uint8(c)  >= uint8(d+1)  && uint8(d+1)  > uint8(d)  => ((Less|Leq)8U  (Const8  <x.Type> [c-d-1]) (Sub8  <x.Type> x (Const8  <x.Type> [d+1])))
   367  
   368  // single bit difference: ( x != c && x != d ) -> ( x|(c^d) != c )
   369  (AndB (Neq(64|32|16|8) x cv:(Const(64|32|16|8) [c])) (Neq(64|32|16|8) x (Const(64|32|16|8) [d]))) && c|d == c && oneBit(c^d) => (Neq(64|32|16|8) (Or(64|32|16|8) <x.Type> x (Const(64|32|16|8) <x.Type> [c^d])) cv)
   370  
   371  // single bit difference: ( x == c || x == d ) -> ( x|(c^d) == c )
   372  (OrB (Eq(64|32|16|8) x cv:(Const(64|32|16|8) [c])) (Eq(64|32|16|8) x (Const(64|32|16|8) [d]))) && c|d == c && oneBit(c^d) => (Eq(64|32|16|8) (Or(64|32|16|8) <x.Type> x (Const(64|32|16|8) <x.Type> [c^d])) cv)
   373  
   374  // NaN check: ( x != x || x (>|>=|<|<=) c ) -> ( !(c (>=|>|<=|<) x) )
   375  (OrB (Neq64F x x) ((Less|Leq)64F x y:(Const64F [c]))) => (Not ((Leq|Less)64F y x))
   376  (OrB (Neq64F x x) ((Less|Leq)64F y:(Const64F [c]) x)) => (Not ((Leq|Less)64F x y))
   377  (OrB (Neq32F x x) ((Less|Leq)32F x y:(Const32F [c]))) => (Not ((Leq|Less)32F y x))
   378  (OrB (Neq32F x x) ((Less|Leq)32F y:(Const32F [c]) x)) => (Not ((Leq|Less)32F x y))
   379  
   380  // NaN check: ( x != x || Abs(x) (>|>=|<|<=) c ) -> ( !(c (>=|>|<=|<) Abs(x) )
   381  (OrB (Neq64F x x) ((Less|Leq)64F abs:(Abs x) y:(Const64F [c]))) => (Not ((Leq|Less)64F y abs))
   382  (OrB (Neq64F x x) ((Less|Leq)64F y:(Const64F [c]) abs:(Abs x))) => (Not ((Leq|Less)64F abs y))
   383  
   384  // NaN check: ( x != x || -x (>|>=|<|<=) c ) -> ( !(c (>=|>|<=|<) -x) )
   385  (OrB (Neq64F x x) ((Less|Leq)64F neg:(Neg64F x) y:(Const64F [c]))) => (Not ((Leq|Less)64F y neg))
   386  (OrB (Neq64F x x) ((Less|Leq)64F y:(Const64F [c]) neg:(Neg64F x))) => (Not ((Leq|Less)64F neg y))
   387  (OrB (Neq32F x x) ((Less|Leq)32F neg:(Neg32F x) y:(Const32F [c]))) => (Not ((Leq|Less)32F y neg))
   388  (OrB (Neq32F x x) ((Less|Leq)32F y:(Const32F [c]) neg:(Neg32F x))) => (Not ((Leq|Less)32F neg y))
   389  
   390  // Canonicalize x-const to x+(-const)
   391  (Sub64 x (Const64 <t> [c])) && x.Op != OpConst64 => (Add64 (Const64 <t> [-c]) x)
   392  (Sub32 x (Const32 <t> [c])) && x.Op != OpConst32 => (Add32 (Const32 <t> [-c]) x)
   393  (Sub16 x (Const16 <t> [c])) && x.Op != OpConst16 => (Add16 (Const16 <t> [-c]) x)
   394  (Sub8  x (Const8  <t> [c])) && x.Op != OpConst8  => (Add8  (Const8  <t> [-c]) x)
   395  
   396  // fold negation into comparison operators
   397  (Not (Eq(64|32|16|8|B|Ptr|64F|32F) x y)) => (Neq(64|32|16|8|B|Ptr|64F|32F) x y)
   398  (Not (Neq(64|32|16|8|B|Ptr|64F|32F) x y)) => (Eq(64|32|16|8|B|Ptr|64F|32F) x y)
   399  
   400  (Not (Less(64|32|16|8) x y)) => (Leq(64|32|16|8) y x)
   401  (Not (Less(64|32|16|8)U x y)) => (Leq(64|32|16|8)U y x)
   402  (Not (Leq(64|32|16|8) x y)) => (Less(64|32|16|8) y x)
   403  (Not (Leq(64|32|16|8)U x y)) => (Less(64|32|16|8)U y x)
   404  
   405  // Distribute multiplication c * (d+x) -> c*d + c*x. Useful for:
   406  // a[i].b = ...; a[i+1].b = ...
   407  // The !isPowerOfTwo is a kludge to keep a[i+1] using an index by a multiply,
   408  // which turns into an index by a shift, which can use a shifted operand on ARM systems.
   409  (Mul64 (Const64 <t> [c]) (Add64 <t> (Const64 <t> [d]) x)) && !isPowerOfTwo(c) =>
   410    (Add64 (Const64 <t> [c*d]) (Mul64 <t> (Const64 <t> [c]) x))
   411  (Mul32 (Const32 <t> [c]) (Add32 <t> (Const32 <t> [d]) x)) && !isPowerOfTwo(c) =>
   412    (Add32 (Const32 <t> [c*d]) (Mul32 <t> (Const32 <t> [c]) x))
   413  (Mul16 (Const16 <t> [c]) (Add16 <t> (Const16 <t> [d]) x)) && !isPowerOfTwo(c) =>
   414    (Add16 (Const16 <t> [c*d]) (Mul16 <t> (Const16 <t> [c]) x))
   415  (Mul8 (Const8 <t> [c]) (Add8 <t> (Const8 <t> [d]) x)) && !isPowerOfTwo(c) =>
   416    (Add8 (Const8 <t> [c*d]) (Mul8 <t> (Const8 <t> [c]) x))
   417  
   418  // Rewrite x*y ± x*z  to  x*(y±z)
   419  (Add(64|32|16|8) <t> (Mul(64|32|16|8) x y) (Mul(64|32|16|8) x z))
   420  	=> (Mul(64|32|16|8) x (Add(64|32|16|8) <t> y z))
   421  (Sub(64|32|16|8) <t> (Mul(64|32|16|8) x y) (Mul(64|32|16|8) x z))
   422  	=> (Mul(64|32|16|8) x (Sub(64|32|16|8) <t> y z))
   423  
   424  // Canonicalize x+x to x << 1.
   425  // This is often slower since most CPUs have more adders than shifters, but it can enable other optimizations.
   426  // Arches who care about this like AMD64 convert x << 1 back to x+x in their arch-specific rules which is useful anyhow.
   427  (Add(64|32|16|8) x x) => (Lsh(64|32|16|8)x64 x (Const64 <types.Types[types.TUINT64]> [1]))
   428  
   429  // rewrite shifts of 8/16/32 bit consts into 64 bit consts to reduce
   430  // the number of the other rewrite rules for const shifts
   431  (Lsh64x32  <t> x (Const32 [c])) => (Lsh64x64  x (Const64 <t> [int64(uint32(c))]))
   432  (Lsh64x16  <t> x (Const16 [c])) => (Lsh64x64  x (Const64 <t> [int64(uint16(c))]))
   433  (Lsh64x8   <t> x (Const8  [c])) => (Lsh64x64  x (Const64 <t> [int64(uint8(c))]))
   434  (Rsh64x32  <t> x (Const32 [c])) => (Rsh64x64  x (Const64 <t> [int64(uint32(c))]))
   435  (Rsh64x16  <t> x (Const16 [c])) => (Rsh64x64  x (Const64 <t> [int64(uint16(c))]))
   436  (Rsh64x8   <t> x (Const8  [c])) => (Rsh64x64  x (Const64 <t> [int64(uint8(c))]))
   437  (Rsh64Ux32 <t> x (Const32 [c])) => (Rsh64Ux64 x (Const64 <t> [int64(uint32(c))]))
   438  (Rsh64Ux16 <t> x (Const16 [c])) => (Rsh64Ux64 x (Const64 <t> [int64(uint16(c))]))
   439  (Rsh64Ux8  <t> x (Const8  [c])) => (Rsh64Ux64 x (Const64 <t> [int64(uint8(c))]))
   440  
   441  (Lsh32x32  <t> x (Const32 [c])) => (Lsh32x64  x (Const64 <t> [int64(uint32(c))]))
   442  (Lsh32x16  <t> x (Const16 [c])) => (Lsh32x64  x (Const64 <t> [int64(uint16(c))]))
   443  (Lsh32x8   <t> x (Const8  [c])) => (Lsh32x64  x (Const64 <t> [int64(uint8(c))]))
   444  (Rsh32x32  <t> x (Const32 [c])) => (Rsh32x64  x (Const64 <t> [int64(uint32(c))]))
   445  (Rsh32x16  <t> x (Const16 [c])) => (Rsh32x64  x (Const64 <t> [int64(uint16(c))]))
   446  (Rsh32x8   <t> x (Const8  [c])) => (Rsh32x64  x (Const64 <t> [int64(uint8(c))]))
   447  (Rsh32Ux32 <t> x (Const32 [c])) => (Rsh32Ux64 x (Const64 <t> [int64(uint32(c))]))
   448  (Rsh32Ux16 <t> x (Const16 [c])) => (Rsh32Ux64 x (Const64 <t> [int64(uint16(c))]))
   449  (Rsh32Ux8  <t> x (Const8  [c])) => (Rsh32Ux64 x (Const64 <t> [int64(uint8(c))]))
   450  
   451  (Lsh16x32  <t> x (Const32 [c])) => (Lsh16x64  x (Const64 <t> [int64(uint32(c))]))
   452  (Lsh16x16  <t> x (Const16 [c])) => (Lsh16x64  x (Const64 <t> [int64(uint16(c))]))
   453  (Lsh16x8   <t> x (Const8  [c])) => (Lsh16x64  x (Const64 <t> [int64(uint8(c))]))
   454  (Rsh16x32  <t> x (Const32 [c])) => (Rsh16x64  x (Const64 <t> [int64(uint32(c))]))
   455  (Rsh16x16  <t> x (Const16 [c])) => (Rsh16x64  x (Const64 <t> [int64(uint16(c))]))
   456  (Rsh16x8   <t> x (Const8  [c])) => (Rsh16x64  x (Const64 <t> [int64(uint8(c))]))
   457  (Rsh16Ux32 <t> x (Const32 [c])) => (Rsh16Ux64 x (Const64 <t> [int64(uint32(c))]))
   458  (Rsh16Ux16 <t> x (Const16 [c])) => (Rsh16Ux64 x (Const64 <t> [int64(uint16(c))]))
   459  (Rsh16Ux8  <t> x (Const8  [c])) => (Rsh16Ux64 x (Const64 <t> [int64(uint8(c))]))
   460  
   461  (Lsh8x32  <t> x (Const32 [c])) => (Lsh8x64  x (Const64 <t> [int64(uint32(c))]))
   462  (Lsh8x16  <t> x (Const16 [c])) => (Lsh8x64  x (Const64 <t> [int64(uint16(c))]))
   463  (Lsh8x8   <t> x (Const8  [c])) => (Lsh8x64  x (Const64 <t> [int64(uint8(c))]))
   464  (Rsh8x32  <t> x (Const32 [c])) => (Rsh8x64  x (Const64 <t> [int64(uint32(c))]))
   465  (Rsh8x16  <t> x (Const16 [c])) => (Rsh8x64  x (Const64 <t> [int64(uint16(c))]))
   466  (Rsh8x8   <t> x (Const8  [c])) => (Rsh8x64  x (Const64 <t> [int64(uint8(c))]))
   467  (Rsh8Ux32 <t> x (Const32 [c])) => (Rsh8Ux64 x (Const64 <t> [int64(uint32(c))]))
   468  (Rsh8Ux16 <t> x (Const16 [c])) => (Rsh8Ux64 x (Const64 <t> [int64(uint16(c))]))
   469  (Rsh8Ux8  <t> x (Const8  [c])) => (Rsh8Ux64 x (Const64 <t> [int64(uint8(c))]))
   470  
   471  // shifts by zero
   472  (Lsh(64|32|16|8)x64  x (Const64 [0])) => x
   473  (Rsh(64|32|16|8)x64  x (Const64 [0])) => x
   474  (Rsh(64|32|16|8)Ux64 x (Const64 [0])) => x
   475  
   476  // rotates by multiples of register width
   477  (RotateLeft64 x (Const64 [c])) && c%64 == 0 => x
   478  (RotateLeft32 x (Const32 [c])) && c%32 == 0 => x
   479  (RotateLeft16 x (Const16 [c])) && c%16 == 0 => x
   480  (RotateLeft8  x (Const8 [c]))  && c%8  == 0 => x
   481  
   482  // zero shifted
   483  (Lsh64x(64|32|16|8)  (Const64 [0]) _) => (Const64 [0])
   484  (Rsh64x(64|32|16|8)  (Const64 [0]) _) => (Const64 [0])
   485  (Rsh64Ux(64|32|16|8) (Const64 [0]) _) => (Const64 [0])
   486  (Lsh32x(64|32|16|8)  (Const32 [0]) _) => (Const32 [0])
   487  (Rsh32x(64|32|16|8)  (Const32 [0]) _) => (Const32 [0])
   488  (Rsh32Ux(64|32|16|8) (Const32 [0]) _) => (Const32 [0])
   489  (Lsh16x(64|32|16|8)  (Const16 [0]) _) => (Const16 [0])
   490  (Rsh16x(64|32|16|8)  (Const16 [0]) _) => (Const16 [0])
   491  (Rsh16Ux(64|32|16|8) (Const16 [0]) _) => (Const16 [0])
   492  (Lsh8x(64|32|16|8)   (Const8  [0]) _) => (Const8  [0])
   493  (Rsh8x(64|32|16|8)   (Const8  [0]) _) => (Const8  [0])
   494  (Rsh8Ux(64|32|16|8)  (Const8  [0]) _) => (Const8  [0])
   495  
   496  // large left shifts of all values, and right shifts of unsigned values
   497  ((Lsh64|Rsh64U)x64  _ (Const64 [c])) && uint64(c) >= 64 => (Const64 [0])
   498  ((Lsh32|Rsh32U)x64  _ (Const64 [c])) && uint64(c) >= 32 => (Const32 [0])
   499  ((Lsh16|Rsh16U)x64  _ (Const64 [c])) && uint64(c) >= 16 => (Const16 [0])
   500  ((Lsh8|Rsh8U)x64    _ (Const64 [c])) && uint64(c) >= 8  => (Const8  [0])
   501  
   502  // combine const shifts
   503  (Lsh64x64 <t> (Lsh64x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh64x64 x (Const64 <t> [c+d]))
   504  (Lsh32x64 <t> (Lsh32x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh32x64 x (Const64 <t> [c+d]))
   505  (Lsh16x64 <t> (Lsh16x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh16x64 x (Const64 <t> [c+d]))
   506  (Lsh8x64  <t> (Lsh8x64  x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh8x64  x (Const64 <t> [c+d]))
   507  
   508  (Rsh64x64 <t> (Rsh64x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh64x64 x (Const64 <t> [c+d]))
   509  (Rsh32x64 <t> (Rsh32x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh32x64 x (Const64 <t> [c+d]))
   510  (Rsh16x64 <t> (Rsh16x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh16x64 x (Const64 <t> [c+d]))
   511  (Rsh8x64  <t> (Rsh8x64  x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh8x64  x (Const64 <t> [c+d]))
   512  
   513  (Rsh64Ux64 <t> (Rsh64Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh64Ux64 x (Const64 <t> [c+d]))
   514  (Rsh32Ux64 <t> (Rsh32Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh32Ux64 x (Const64 <t> [c+d]))
   515  (Rsh16Ux64 <t> (Rsh16Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh16Ux64 x (Const64 <t> [c+d]))
   516  (Rsh8Ux64  <t> (Rsh8Ux64  x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh8Ux64  x (Const64 <t> [c+d]))
   517  
   518  // Remove signed right shift before an unsigned right shift that extracts the sign bit.
   519  (Rsh8Ux64  (Rsh8x64  x _) (Const64 <t> [7] )) => (Rsh8Ux64  x (Const64 <t> [7] ))
   520  (Rsh16Ux64 (Rsh16x64 x _) (Const64 <t> [15])) => (Rsh16Ux64 x (Const64 <t> [15]))
   521  (Rsh32Ux64 (Rsh32x64 x _) (Const64 <t> [31])) => (Rsh32Ux64 x (Const64 <t> [31]))
   522  (Rsh64Ux64 (Rsh64x64 x _) (Const64 <t> [63])) => (Rsh64Ux64 x (Const64 <t> [63]))
   523  
   524  // Convert x>>c<<c to x&^(1<<c-1)
   525  (Lsh64x64 i:(Rsh(64|64U)x64  x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 64 && i.Uses == 1 => (And64 x (Const64 <v.Type> [int64(-1) << c]))
   526  (Lsh32x64 i:(Rsh(32|32U)x64  x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 32 && i.Uses == 1 => (And32 x (Const32 <v.Type> [int32(-1) << c]))
   527  (Lsh16x64 i:(Rsh(16|16U)x64  x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 16 && i.Uses == 1 => (And16 x (Const16 <v.Type> [int16(-1) << c]))
   528  (Lsh8x64  i:(Rsh(8|8U)x64    x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 8  && i.Uses == 1 => (And8  x (Const8  <v.Type> [int8(-1)  << c]))
   529  // similarly for x<<c>>c
   530  (Rsh64Ux64 i:(Lsh64x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 64 && i.Uses == 1 => (And64 x (Const64 <v.Type> [int64(^uint64(0)>>c)]))
   531  (Rsh32Ux64 i:(Lsh32x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 32 && i.Uses == 1 => (And32 x (Const32 <v.Type> [int32(^uint32(0)>>c)]))
   532  (Rsh16Ux64 i:(Lsh16x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 16 && i.Uses == 1 => (And16 x (Const16 <v.Type> [int16(^uint16(0)>>c)]))
   533  (Rsh8Ux64  i:(Lsh8x64  x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 8  && i.Uses == 1 => (And8  x (Const8  <v.Type> [int8 (^uint8 (0)>>c)]))
   534  
   535  // ((x >> c1) << c2) >> c3
   536  (Rsh(64|32|16|8)Ux64 (Lsh(64|32|16|8)x64 (Rsh(64|32|16|8)Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3]))
   537    && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3)
   538    => (Rsh(64|32|16|8)Ux64 x (Const64 <typ.UInt64> [c1-c2+c3]))
   539  
   540  // ((x << c1) >> c2) << c3
   541  (Lsh(64|32|16|8)x64 (Rsh(64|32|16|8)Ux64 (Lsh(64|32|16|8)x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3]))
   542    && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3)
   543    => (Lsh(64|32|16|8)x64 x (Const64 <typ.UInt64> [c1-c2+c3]))
   544  
   545  // (x >> c) & uppermask = 0
   546  (And64 (Const64 [m]) (Rsh64Ux64 _ (Const64 [c]))) && c >= int64(64-ntz64(m)) => (Const64 [0])
   547  (And32 (Const32 [m]) (Rsh32Ux64 _ (Const64 [c]))) && c >= int64(32-ntz32(m)) => (Const32 [0])
   548  (And16 (Const16 [m]) (Rsh16Ux64 _ (Const64 [c]))) && c >= int64(16-ntz16(m)) => (Const16 [0])
   549  (And8  (Const8  [m]) (Rsh8Ux64  _ (Const64 [c]))) && c >= int64(8-ntz8(m))  => (Const8  [0])
   550  
   551  // (x << c) & lowermask = 0
   552  (And64 (Const64 [m]) (Lsh64x64  _ (Const64 [c]))) && c >= int64(64-nlz64(m)) => (Const64 [0])
   553  (And32 (Const32 [m]) (Lsh32x64  _ (Const64 [c]))) && c >= int64(32-nlz32(m)) => (Const32 [0])
   554  (And16 (Const16 [m]) (Lsh16x64  _ (Const64 [c]))) && c >= int64(16-nlz16(m)) => (Const16 [0])
   555  (And8  (Const8  [m]) (Lsh8x64   _ (Const64 [c]))) && c >= int64(8-nlz8(m))  => (Const8  [0])
   556  
   557  // replace shifts with zero extensions
   558  (Rsh16Ux64 (Lsh16x64 x (Const64  [8])) (Const64  [8])) => (ZeroExt8to16  (Trunc16to8  <typ.UInt8>  x))
   559  (Rsh32Ux64 (Lsh32x64 x (Const64 [24])) (Const64 [24])) => (ZeroExt8to32  (Trunc32to8  <typ.UInt8>  x))
   560  (Rsh64Ux64 (Lsh64x64 x (Const64 [56])) (Const64 [56])) => (ZeroExt8to64  (Trunc64to8  <typ.UInt8>  x))
   561  (Rsh32Ux64 (Lsh32x64 x (Const64 [16])) (Const64 [16])) => (ZeroExt16to32 (Trunc32to16 <typ.UInt16> x))
   562  (Rsh64Ux64 (Lsh64x64 x (Const64 [48])) (Const64 [48])) => (ZeroExt16to64 (Trunc64to16 <typ.UInt16> x))
   563  (Rsh64Ux64 (Lsh64x64 x (Const64 [32])) (Const64 [32])) => (ZeroExt32to64 (Trunc64to32 <typ.UInt32> x))
   564  
   565  // replace shifts with sign extensions
   566  (Rsh16x64 (Lsh16x64 x (Const64  [8])) (Const64  [8])) => (SignExt8to16  (Trunc16to8  <typ.Int8>  x))
   567  (Rsh32x64 (Lsh32x64 x (Const64 [24])) (Const64 [24])) => (SignExt8to32  (Trunc32to8  <typ.Int8>  x))
   568  (Rsh64x64 (Lsh64x64 x (Const64 [56])) (Const64 [56])) => (SignExt8to64  (Trunc64to8  <typ.Int8>  x))
   569  (Rsh32x64 (Lsh32x64 x (Const64 [16])) (Const64 [16])) => (SignExt16to32 (Trunc32to16 <typ.Int16> x))
   570  (Rsh64x64 (Lsh64x64 x (Const64 [48])) (Const64 [48])) => (SignExt16to64 (Trunc64to16 <typ.Int16> x))
   571  (Rsh64x64 (Lsh64x64 x (Const64 [32])) (Const64 [32])) => (SignExt32to64 (Trunc64to32 <typ.Int32> x))
   572  
   573  // ((x >> c) & d) << e
   574  (Lsh64x64 (And64 (Rsh(64|64U)x64 <t> x (Const64 <t2> [c])) (Const64 [d])) (Const64 [e])) && c >= e => (And64 (Rsh(64|64U)x64 <t> x (Const64 <t2> [c-e])) (Const64 <t> [d<<e]))
   575  (Lsh32x64 (And32 (Rsh(32|32U)x64 <t> x (Const64 <t2> [c])) (Const32 [d])) (Const64 [e])) && c >= e => (And32 (Rsh(32|32U)x64 <t> x (Const64 <t2> [c-e])) (Const32 <t> [d<<e]))
   576  (Lsh16x64 (And16 (Rsh(16|16U)x64 <t> x (Const64 <t2> [c])) (Const16 [d])) (Const64 [e])) && c >= e => (And16 (Rsh(16|16U)x64 <t> x (Const64 <t2> [c-e])) (Const16 <t> [d<<e]))
   577  (Lsh8x64  (And8  (Rsh(8|8U)x64   <t> x (Const64 <t2> [c])) (Const8  [d])) (Const64 [e])) && c >= e => (And8  (Rsh(8|8U)x64   <t> x (Const64 <t2> [c-e])) (Const8  <t> [d<<e]))
   578  (Lsh64x64 (And64 (Rsh(64|64U)x64 <t> x (Const64 <t2> [c])) (Const64 [d])) (Const64 [e])) && c < e =>  (And64 (Lsh64x64 <t> x (Const64 <t2> [e-c])) (Const64 <t> [d<<e]))
   579  (Lsh32x64 (And32 (Rsh(32|32U)x64 <t> x (Const64 <t2> [c])) (Const32 [d])) (Const64 [e])) && c < e =>  (And32 (Lsh32x64 <t> x (Const64 <t2> [e-c])) (Const32 <t> [d<<e]))
   580  (Lsh16x64 (And16 (Rsh(16|16U)x64 <t> x (Const64 <t2> [c])) (Const16 [d])) (Const64 [e])) && c < e =>  (And16 (Lsh16x64 <t> x (Const64 <t2> [e-c])) (Const16 <t> [d<<e]))
   581  (Lsh8x64  (And8  (Rsh(8|8U)x64   <t> x (Const64 <t2> [c])) (Const8  [d])) (Const64 [e])) && c < e =>  (And8  (Lsh8x64  <t> x (Const64 <t2> [e-c])) (Const8  <t> [d<<e]))
   582  
   583  // constant comparisons
   584  (Eq(64|32|16|8)   (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c == d])
   585  (Neq(64|32|16|8)  (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c != d])
   586  (Less(64|32|16|8) (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c < d])
   587  (Leq(64|32|16|8)  (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c <= d])
   588  
   589  (Less64U (Const64 [c]) (Const64 [d])) => (ConstBool [uint64(c) < uint64(d)])
   590  (Less32U (Const32 [c]) (Const32 [d])) => (ConstBool [uint32(c) < uint32(d)])
   591  (Less16U (Const16 [c]) (Const16 [d])) => (ConstBool [uint16(c) < uint16(d)])
   592  (Less8U  (Const8  [c]) (Const8  [d])) => (ConstBool [ uint8(c) <  uint8(d)])
   593  
   594  (Leq64U (Const64 [c]) (Const64 [d])) => (ConstBool [uint64(c) <= uint64(d)])
   595  (Leq32U (Const32 [c]) (Const32 [d])) => (ConstBool [uint32(c) <= uint32(d)])
   596  (Leq16U (Const16 [c]) (Const16 [d])) => (ConstBool [uint16(c) <= uint16(d)])
   597  (Leq8U  (Const8  [c]) (Const8  [d])) => (ConstBool [ uint8(c) <=  uint8(d)])
   598  
   599  (Leq8  (Const8  [0]) (And8  _ (Const8  [c]))) && c >= 0 => (ConstBool [true])
   600  (Leq16 (Const16 [0]) (And16 _ (Const16 [c]))) && c >= 0 => (ConstBool [true])
   601  (Leq32 (Const32 [0]) (And32 _ (Const32 [c]))) && c >= 0 => (ConstBool [true])
   602  (Leq64 (Const64 [0]) (And64 _ (Const64 [c]))) && c >= 0 => (ConstBool [true])
   603  
   604  (Leq8  (Const8  [0]) (Rsh8Ux64  _ (Const64 [c]))) && c > 0 => (ConstBool [true])
   605  (Leq16 (Const16 [0]) (Rsh16Ux64 _ (Const64 [c]))) && c > 0 => (ConstBool [true])
   606  (Leq32 (Const32 [0]) (Rsh32Ux64 _ (Const64 [c]))) && c > 0 => (ConstBool [true])
   607  (Leq64 (Const64 [0]) (Rsh64Ux64 _ (Const64 [c]))) && c > 0 => (ConstBool [true])
   608  
   609  // prefer equalities with zero
   610  (Less(64|32|16|8) (Const(64|32|16|8) <t> [0]) x) && isNonNegative(x) => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
   611  (Less(64|32|16|8) x (Const(64|32|16|8) <t> [1])) && isNonNegative(x) => (Eq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
   612  (Less(64|32|16|8)U x (Const(64|32|16|8) <t> [1])) => (Eq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
   613  (Leq(64|32|16|8)U (Const(64|32|16|8) <t> [1]) x) => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
   614  
   615  // prefer comparisons with zero
   616  (Less(64|32|16|8) x (Const(64|32|16|8) <t> [1])) => (Leq(64|32|16|8) x (Const(64|32|16|8) <t> [0]))
   617  (Leq(64|32|16|8) x (Const(64|32|16|8) <t> [-1])) => (Less(64|32|16|8) x (Const(64|32|16|8) <t> [0]))
   618  (Leq(64|32|16|8) (Const(64|32|16|8) <t> [1]) x) => (Less(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
   619  (Less(64|32|16|8) (Const(64|32|16|8) <t> [-1]) x) => (Leq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
   620  
   621  // constant floating point comparisons
   622  (Eq32F   (Const32F [c]) (Const32F [d])) => (ConstBool [c == d])
   623  (Eq64F   (Const64F [c]) (Const64F [d])) => (ConstBool [c == d])
   624  (Neq32F  (Const32F [c]) (Const32F [d])) => (ConstBool [c != d])
   625  (Neq64F  (Const64F [c]) (Const64F [d])) => (ConstBool [c != d])
   626  (Less32F (Const32F [c]) (Const32F [d])) => (ConstBool [c < d])
   627  (Less64F (Const64F [c]) (Const64F [d])) => (ConstBool [c < d])
   628  (Leq32F  (Const32F [c]) (Const32F [d])) => (ConstBool [c <= d])
   629  (Leq64F  (Const64F [c]) (Const64F [d])) => (ConstBool [c <= d])
   630  
   631  // simplifications
   632  (Or(64|32|16|8) x x) => x
   633  (Or(64|32|16|8) (Const(64|32|16|8)  [0]) x) => x
   634  (Or(64|32|16|8) (Const(64|32|16|8) [-1]) _) => (Const(64|32|16|8) [-1])
   635  (Or(64|32|16|8) (Com(64|32|16|8)     x)  x) => (Const(64|32|16|8) [-1])
   636  
   637  (And(64|32|16|8) x x) => x
   638  (And(64|32|16|8) (Const(64|32|16|8) [-1]) x) => x
   639  (And(64|32|16|8) (Const(64|32|16|8)  [0]) _) => (Const(64|32|16|8) [0])
   640  (And(64|32|16|8) (Com(64|32|16|8)     x)  x) => (Const(64|32|16|8) [0])
   641  
   642  (Xor(64|32|16|8) x x) => (Const(64|32|16|8) [0])
   643  (Xor(64|32|16|8) (Const(64|32|16|8) [0]) x) => x
   644  (Xor(64|32|16|8) (Com(64|32|16|8)    x)  x) => (Const(64|32|16|8) [-1])
   645  
   646  (Add(64|32|16|8) (Const(64|32|16|8) [0]) x) => x
   647  (Sub(64|32|16|8) x x) => (Const(64|32|16|8) [0])
   648  (Mul(64|32|16|8) (Const(64|32|16|8) [0]) _) => (Const(64|32|16|8) [0])
   649  (Mul(64|32)uover <t> (Const(64|32) [0]) x) => (MakeTuple (Const(64|32) <t.FieldType(0)> [0]) (ConstBool <t.FieldType(1)> [false]))
   650  
   651  (Com(64|32|16|8) (Com(64|32|16|8)  x)) => x
   652  (Com(64|32|16|8) (Const(64|32|16|8) [c])) => (Const(64|32|16|8) [^c])
   653  
   654  (Neg(64|32|16|8) (Sub(64|32|16|8) x y)) => (Sub(64|32|16|8) y x)
   655  (Add(64|32|16|8) x (Neg(64|32|16|8) y)) => (Sub(64|32|16|8) x y)
   656  
   657  (Xor(64|32|16|8) (Const(64|32|16|8) [-1]) x) => (Com(64|32|16|8) x)
   658  
   659  (Sub(64|32|16|8) (Neg(64|32|16|8) x) (Com(64|32|16|8) x)) => (Const(64|32|16|8) [1])
   660  (Sub(64|32|16|8) (Com(64|32|16|8) x) (Neg(64|32|16|8) x)) => (Const(64|32|16|8) [-1])
   661  (Add(64|32|16|8) (Com(64|32|16|8) x)                  x)  => (Const(64|32|16|8) [-1])
   662  
   663  // Prove does not simplify this because x + y might overflow into carry,
   664  // however if no one care about the carry, let it overflow in a normal add.
   665  (Select0 a:(Add64carry x y (Const64 [0]))) && a.Uses == 1 => (Add64 x y)
   666  
   667  // Simplification when involving common integer
   668  // (t + x) - (t + y) == x - y
   669  // (t + x) - (y + t) == x - y
   670  // (x + t) - (y + t) == x - y
   671  // (x + t) - (t + y) == x - y
   672  // (x - t) + (t + y) == x + y
   673  // (x - t) + (y + t) == x + y
   674  (Sub(64|32|16|8) (Add(64|32|16|8) t x) (Add(64|32|16|8) t y)) => (Sub(64|32|16|8) x y)
   675  (Add(64|32|16|8) (Sub(64|32|16|8) x t) (Add(64|32|16|8) t y)) => (Add(64|32|16|8) x y)
   676  
   677  // ^(x-1) == ^x+1 == -x
   678  (Add(64|32|16|8) (Const(64|32|16|8) [1]) (Com(64|32|16|8) x)) => (Neg(64|32|16|8) x)
   679  (Com(64|32|16|8) (Add(64|32|16|8) (Const(64|32|16|8) [-1]) x)) => (Neg(64|32|16|8) x)
   680  
   681  // -(-x) == x
   682  (Neg(64|32|16|8) (Neg(64|32|16|8) x)) => x
   683  
   684  // -^x == x+1
   685  (Neg(64|32|16|8) <t> (Com(64|32|16|8) x)) => (Add(64|32|16|8) (Const(64|32|16|8) <t> [1]) x)
   686  
   687  (And(64|32|16|8) x (And(64|32|16|8) x y)) => (And(64|32|16|8) x y)
   688  (Or(64|32|16|8) x (Or(64|32|16|8) x y)) => (Or(64|32|16|8) x y)
   689  (Xor(64|32|16|8) x (Xor(64|32|16|8) x y)) => y
   690  
   691  // Fold comparisons with numeric bounds
   692  (Less(64|32|16|8)U _ (Const(64|32|16|8) [0]))  => (ConstBool [false])
   693  (Leq(64|32|16|8)U (Const(64|32|16|8) [0]) _)   => (ConstBool [true])
   694  (Less(64|32|16|8)U (Const(64|32|16|8) [-1]) _) => (ConstBool [false])
   695  (Leq(64|32|16|8)U _ (Const(64|32|16|8) [-1]))  => (ConstBool [true])
   696  (Less64 _ (Const64 [math.MinInt64])) => (ConstBool [false])
   697  (Less32 _ (Const32 [math.MinInt32])) => (ConstBool [false])
   698  (Less16 _ (Const16 [math.MinInt16])) => (ConstBool [false])
   699  (Less8  _ (Const8  [math.MinInt8 ])) => (ConstBool [false])
   700  (Leq64 (Const64 [math.MinInt64]) _)  => (ConstBool [true])
   701  (Leq32 (Const32 [math.MinInt32]) _)  => (ConstBool [true])
   702  (Leq16 (Const16 [math.MinInt16]) _)  => (ConstBool [true])
   703  (Leq8  (Const8  [math.MinInt8 ]) _)  => (ConstBool [true])
   704  (Less64 (Const64 [math.MaxInt64]) _) => (ConstBool [false])
   705  (Less32 (Const32 [math.MaxInt32]) _) => (ConstBool [false])
   706  (Less16 (Const16 [math.MaxInt16]) _) => (ConstBool [false])
   707  (Less8  (Const8  [math.MaxInt8 ]) _) => (ConstBool [false])
   708  (Leq64 _ (Const64 [math.MaxInt64]))  => (ConstBool [true])
   709  (Leq32 _ (Const32 [math.MaxInt32]))  => (ConstBool [true])
   710  (Leq16 _ (Const16 [math.MaxInt16]))  => (ConstBool [true])
   711  (Leq8  _ (Const8  [math.MaxInt8 ]))  => (ConstBool [true])
   712  
   713  // Canonicalize <= on numeric bounds and < near numeric bounds to ==
   714  (Leq(64|32|16|8)U x c:(Const(64|32|16|8) [0]))     => (Eq(64|32|16|8) x c)
   715  (Leq(64|32|16|8)U c:(Const(64|32|16|8) [-1]) x)    => (Eq(64|32|16|8) x c)
   716  (Less(64|32|16|8)U x (Const(64|32|16|8) <t> [1]))  => (Eq(64|32|16|8) x (Const(64|32|16|8) <t> [0]))
   717  (Less(64|32|16|8)U (Const(64|32|16|8) <t> [-2]) x) => (Eq(64|32|16|8) x (Const(64|32|16|8) <t> [-1]))
   718  (Leq64 x c:(Const64 [math.MinInt64])) => (Eq64 x c)
   719  (Leq32 x c:(Const32 [math.MinInt32])) => (Eq32 x c)
   720  (Leq16 x c:(Const16 [math.MinInt16])) => (Eq16 x c)
   721  (Leq8  x c:(Const8  [math.MinInt8 ])) => (Eq8  x c)
   722  (Leq64 c:(Const64 [math.MaxInt64]) x) => (Eq64 x c)
   723  (Leq32 c:(Const32 [math.MaxInt32]) x) => (Eq32 x c)
   724  (Leq16 c:(Const16 [math.MaxInt16]) x) => (Eq16 x c)
   725  (Leq8  c:(Const8  [math.MaxInt8 ]) x) => (Eq8  x c)
   726  (Less64 x (Const64 <t> [math.MinInt64+1])) => (Eq64 x (Const64 <t> [math.MinInt64]))
   727  (Less32 x (Const32 <t> [math.MinInt32+1])) => (Eq32 x (Const32 <t> [math.MinInt32]))
   728  (Less16 x (Const16 <t> [math.MinInt16+1])) => (Eq16 x (Const16 <t> [math.MinInt16]))
   729  (Less8  x (Const8  <t> [math.MinInt8 +1])) => (Eq8  x (Const8  <t> [math.MinInt8 ]))
   730  (Less64 (Const64 <t> [math.MaxInt64-1]) x) => (Eq64 x (Const64 <t> [math.MaxInt64]))
   731  (Less32 (Const32 <t> [math.MaxInt32-1]) x) => (Eq32 x (Const32 <t> [math.MaxInt32]))
   732  (Less16 (Const16 <t> [math.MaxInt16-1]) x) => (Eq16 x (Const16 <t> [math.MaxInt16]))
   733  (Less8  (Const8  <t> [math.MaxInt8 -1]) x) => (Eq8  x (Const8  <t> [math.MaxInt8 ]))
   734  
   735  // Ands clear bits. Ors set bits.
   736  // If a subsequent Or will set all the bits
   737  // that an And cleared, we can skip the And.
   738  // This happens in bitmasking code like:
   739  //   x &^= 3 << shift // clear two old bits
   740  //   x  |= v << shift // set two new bits
   741  // when shift is a small constant and v ends up a constant 3.
   742  (Or8  (And8  x (Const8  [c2])) (Const8  <t> [c1])) && ^(c1 | c2) == 0 => (Or8  (Const8  <t> [c1]) x)
   743  (Or16 (And16 x (Const16 [c2])) (Const16 <t> [c1])) && ^(c1 | c2) == 0 => (Or16 (Const16 <t> [c1]) x)
   744  (Or32 (And32 x (Const32 [c2])) (Const32 <t> [c1])) && ^(c1 | c2) == 0 => (Or32 (Const32 <t> [c1]) x)
   745  (Or64 (And64 x (Const64 [c2])) (Const64 <t> [c1])) && ^(c1 | c2) == 0 => (Or64 (Const64 <t> [c1]) x)
   746  
   747  (Trunc64to8  (And64 (Const64 [y]) x)) && y&0xFF == 0xFF => (Trunc64to8 x)
   748  (Trunc64to16 (And64 (Const64 [y]) x)) && y&0xFFFF == 0xFFFF => (Trunc64to16 x)
   749  (Trunc64to32 (And64 (Const64 [y]) x)) && y&0xFFFFFFFF == 0xFFFFFFFF => (Trunc64to32 x)
   750  (Trunc32to8  (And32 (Const32 [y]) x)) && y&0xFF == 0xFF => (Trunc32to8 x)
   751  (Trunc32to16 (And32 (Const32 [y]) x)) && y&0xFFFF == 0xFFFF => (Trunc32to16 x)
   752  (Trunc16to8  (And16 (Const16 [y]) x)) && y&0xFF == 0xFF => (Trunc16to8 x)
   753  
   754  (ZeroExt8to64  (Trunc64to8  x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 56 => x
   755  (ZeroExt16to64 (Trunc64to16 x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 48 => x
   756  (ZeroExt32to64 (Trunc64to32 x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 32 => x
   757  (ZeroExt8to32  (Trunc32to8  x:(Rsh32Ux64 _ (Const64 [s])))) && s >= 24 => x
   758  (ZeroExt16to32 (Trunc32to16 x:(Rsh32Ux64 _ (Const64 [s])))) && s >= 16 => x
   759  (ZeroExt8to16  (Trunc16to8  x:(Rsh16Ux64 _ (Const64 [s])))) && s >= 8 => x
   760  
   761  (SignExt8to64  (Trunc64to8  x:(Rsh64x64 _ (Const64 [s])))) && s >= 56 => x
   762  (SignExt16to64 (Trunc64to16 x:(Rsh64x64 _ (Const64 [s])))) && s >= 48 => x
   763  (SignExt32to64 (Trunc64to32 x:(Rsh64x64 _ (Const64 [s])))) && s >= 32 => x
   764  (SignExt8to32  (Trunc32to8  x:(Rsh32x64 _ (Const64 [s])))) && s >= 24 => x
   765  (SignExt16to32 (Trunc32to16 x:(Rsh32x64 _ (Const64 [s])))) && s >= 16 => x
   766  (SignExt8to16  (Trunc16to8  x:(Rsh16x64 _ (Const64 [s])))) && s >= 8 => x
   767  
   768  (Slicemask (Const32 [x])) && x > 0 => (Const32 [-1])
   769  (Slicemask (Const32 [0]))          => (Const32 [0])
   770  (Slicemask (Const64 [x])) && x > 0 => (Const64 [-1])
   771  (Slicemask (Const64 [0]))          => (Const64 [0])
   772  
   773  // simplifications often used for lengths.  e.g. len(s[i:i+5])==5
   774  (Sub(64|32|16|8) (Add(64|32|16|8) x y) x) => y
   775  (Sub(64|32|16|8) (Add(64|32|16|8) x y) y) => x
   776  (Sub(64|32|16|8) (Sub(64|32|16|8) x y) x) => (Neg(64|32|16|8) y)
   777  (Sub(64|32|16|8) x (Add(64|32|16|8) x y)) => (Neg(64|32|16|8) y)
   778  (Add(64|32|16|8) x (Sub(64|32|16|8) y x)) => y
   779  (Add(64|32|16|8) x (Add(64|32|16|8) y (Sub(64|32|16|8) z x))) => (Add(64|32|16|8) y z)
   780  
   781  // basic phi simplifications
   782  (Phi (Const8  [c]) (Const8  [c])) => (Const8  [c])
   783  (Phi (Const16 [c]) (Const16 [c])) => (Const16 [c])
   784  (Phi (Const32 [c]) (Const32 [c])) => (Const32 [c])
   785  (Phi (Const64 [c]) (Const64 [c])) => (Const64 [c])
   786  
   787  // slice and interface comparisons
   788  // The frontend ensures that we can only compare against nil,
   789  // so we need only compare the first word (interface type or slice ptr).
   790  (EqInter x y)  => (EqPtr  (ITab x) (ITab y))
   791  (NeqInter x y) => (NeqPtr (ITab x) (ITab y))
   792  (EqSlice x y)  => (EqPtr  (SlicePtr x) (SlicePtr y))
   793  (NeqSlice x y) => (NeqPtr (SlicePtr x) (SlicePtr y))
   794  
   795  // Load of store of same address, with compatibly typed value and same size
   796  (Load <t1> p1 (Store {t2} p2 x _))
   797  	&& isSamePtr(p1, p2)
   798  	&& copyCompatibleType(t1, x.Type)
   799  	&& t1.Size() == t2.Size()
   800  	=> x
   801  (Load <t1> p1 (Store {t2} p2 _ (Store {t3} p3 x _)))
   802  	&& isSamePtr(p1, p3)
   803  	&& copyCompatibleType(t1, x.Type)
   804  	&& t1.Size() == t3.Size()
   805  	&& disjoint(p3, t3.Size(), p2, t2.Size())
   806  	=> x
   807  (Load <t1> p1 (Store {t2} p2 _ (Store {t3} p3 _ (Store {t4} p4 x _))))
   808  	&& isSamePtr(p1, p4)
   809  	&& copyCompatibleType(t1, x.Type)
   810  	&& t1.Size() == t4.Size()
   811  	&& disjoint(p4, t4.Size(), p2, t2.Size())
   812  	&& disjoint(p4, t4.Size(), p3, t3.Size())
   813  	=> x
   814  (Load <t1> p1 (Store {t2} p2 _ (Store {t3} p3 _ (Store {t4} p4 _ (Store {t5} p5 x _)))))
   815  	&& isSamePtr(p1, p5)
   816  	&& copyCompatibleType(t1, x.Type)
   817  	&& t1.Size() == t5.Size()
   818  	&& disjoint(p5, t5.Size(), p2, t2.Size())
   819  	&& disjoint(p5, t5.Size(), p3, t3.Size())
   820  	&& disjoint(p5, t5.Size(), p4, t4.Size())
   821  	=> x
   822  
   823  // Load from a region just copied by Move can read directly from the source.
   824  (Load <t1> op:(OffPtr [o1] p1) move:(Move [n] p2 src mem))
   825  	&& o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p2)
   826  	&& !isVolatile(src)
   827  	=> @move.Block (Load <t1> (OffPtr <op.Type> [o1] src) mem)
   828  
   829  // Pass constants through math.Float{32,64}bits and math.Float{32,64}frombits
   830  (Load <t1> p1 (Store {t2} p2 (Const64  [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 8 && is64BitFloat(t1) && !math.IsNaN(math.Float64frombits(uint64(x))) => (Const64F [math.Float64frombits(uint64(x))])
   831  (Load <t1> p1 (Store {t2} p2 (Const32  [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 4 && is32BitFloat(t1) && !math.IsNaN(float64(math.Float32frombits(uint32(x)))) => (Const32F [math.Float32frombits(uint32(x))])
   832  (Load <t1> p1 (Store {t2} p2 (Const64F [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 8 && is64BitInt(t1)   => (Const64  [int64(math.Float64bits(x))])
   833  (Load <t1> p1 (Store {t2} p2 (Const32F [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 4 && is32BitInt(t1)   => (Const32  [int32(math.Float32bits(x))])
   834  
   835  // Float Loads up to Zeros so they can be constant folded.
   836  (Load <t1> op:(OffPtr [o1] p1)
   837  	(Store {t2} p2 _
   838  		mem:(Zero [n] p3 _)))
   839  	&& o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p3)
   840  	&& CanSSA(t1)
   841  	&& disjoint(op, t1.Size(), p2, t2.Size())
   842  	=> @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p3) mem)
   843  (Load <t1> op:(OffPtr [o1] p1)
   844  	(Store {t2} p2 _
   845  		(Store {t3} p3 _
   846  			mem:(Zero [n] p4 _))))
   847  	&& o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p4)
   848  	&& CanSSA(t1)
   849  	&& disjoint(op, t1.Size(), p2, t2.Size())
   850  	&& disjoint(op, t1.Size(), p3, t3.Size())
   851  	=> @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p4) mem)
   852  (Load <t1> op:(OffPtr [o1] p1)
   853  	(Store {t2} p2 _
   854  		(Store {t3} p3 _
   855  			(Store {t4} p4 _
   856  				mem:(Zero [n] p5 _)))))
   857  	&& o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p5)
   858  	&& CanSSA(t1)
   859  	&& disjoint(op, t1.Size(), p2, t2.Size())
   860  	&& disjoint(op, t1.Size(), p3, t3.Size())
   861  	&& disjoint(op, t1.Size(), p4, t4.Size())
   862  	=> @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p5) mem)
   863  (Load <t1> op:(OffPtr [o1] p1)
   864  	(Store {t2} p2 _
   865  		(Store {t3} p3 _
   866  			(Store {t4} p4 _
   867  				(Store {t5} p5 _
   868  					mem:(Zero [n] p6 _))))))
   869  	&& o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p6)
   870  	&& CanSSA(t1)
   871  	&& disjoint(op, t1.Size(), p2, t2.Size())
   872  	&& disjoint(op, t1.Size(), p3, t3.Size())
   873  	&& disjoint(op, t1.Size(), p4, t4.Size())
   874  	&& disjoint(op, t1.Size(), p5, t5.Size())
   875  	=> @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p6) mem)
   876  
   877  // Zero to Load forwarding.
   878  (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
   879  	&& t1.IsBoolean()
   880  	&& isSamePtr(p1, p2)
   881  	&& n >= o + 1
   882  	=> (ConstBool [false])
   883  (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
   884  	&& is8BitInt(t1)
   885  	&& isSamePtr(p1, p2)
   886  	&& n >= o + 1
   887  	=> (Const8 [0])
   888  (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
   889  	&& is16BitInt(t1)
   890  	&& isSamePtr(p1, p2)
   891  	&& n >= o + 2
   892  	=> (Const16 [0])
   893  (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
   894  	&& is32BitInt(t1)
   895  	&& isSamePtr(p1, p2)
   896  	&& n >= o + 4
   897  	=> (Const32 [0])
   898  (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
   899  	&& is64BitInt(t1)
   900  	&& isSamePtr(p1, p2)
   901  	&& n >= o + 8
   902  	=> (Const64 [0])
   903  (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
   904  	&& is32BitFloat(t1)
   905  	&& isSamePtr(p1, p2)
   906  	&& n >= o + 4
   907  	=> (Const32F [0])
   908  (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
   909  	&& is64BitFloat(t1)
   910  	&& isSamePtr(p1, p2)
   911  	&& n >= o + 8
   912  	=> (Const64F [0])
   913  
   914  // Eliminate stores of values that have just been loaded from the same location.
   915  // We also handle the common case where there are some intermediate stores.
   916  (Store {t1} p1 (Load <t2> p2 mem) mem)
   917  	&& isSamePtr(p1, p2)
   918  	&& t2.Size() == t1.Size()
   919  	=> mem
   920  (Store {t1} p1 (Load <t2> p2 oldmem) mem:(Store {t3} p3 _ oldmem))
   921  	&& isSamePtr(p1, p2)
   922  	&& t2.Size() == t1.Size()
   923  	&& disjoint(p1, t1.Size(), p3, t3.Size())
   924  	=> mem
   925  (Store {t1} p1 (Load <t2> p2 oldmem) mem:(Store {t3} p3 _ (Store {t4} p4 _ oldmem)))
   926  	&& isSamePtr(p1, p2)
   927  	&& t2.Size() == t1.Size()
   928  	&& disjoint(p1, t1.Size(), p3, t3.Size())
   929  	&& disjoint(p1, t1.Size(), p4, t4.Size())
   930  	=> mem
   931  (Store {t1} p1 (Load <t2> p2 oldmem) mem:(Store {t3} p3 _ (Store {t4} p4 _ (Store {t5} p5 _ oldmem))))
   932  	&& isSamePtr(p1, p2)
   933  	&& t2.Size() == t1.Size()
   934  	&& disjoint(p1, t1.Size(), p3, t3.Size())
   935  	&& disjoint(p1, t1.Size(), p4, t4.Size())
   936  	&& disjoint(p1, t1.Size(), p5, t5.Size())
   937  	=> mem
   938  
   939  // Don't Store zeros to cleared variables.
   940  (Store {t} (OffPtr [o] p1) x mem:(Zero [n] p2 _))
   941  	&& isConstZero(x)
   942  	&& o >= 0 && t.Size() + o <= n && isSamePtr(p1, p2)
   943  	=> mem
   944  (Store {t1} op:(OffPtr [o1] p1) x mem:(Store {t2} p2 _ (Zero [n] p3 _)))
   945  	&& isConstZero(x)
   946  	&& o1 >= 0 && t1.Size() + o1 <= n && isSamePtr(p1, p3)
   947  	&& disjoint(op, t1.Size(), p2, t2.Size())
   948  	=> mem
   949  (Store {t1} op:(OffPtr [o1] p1) x mem:(Store {t2} p2 _ (Store {t3} p3 _ (Zero [n] p4 _))))
   950  	&& isConstZero(x)
   951  	&& o1 >= 0 && t1.Size() + o1 <= n && isSamePtr(p1, p4)
   952  	&& disjoint(op, t1.Size(), p2, t2.Size())
   953  	&& disjoint(op, t1.Size(), p3, t3.Size())
   954  	=> mem
   955  (Store {t1} op:(OffPtr [o1] p1) x mem:(Store {t2} p2 _ (Store {t3} p3 _ (Store {t4} p4 _ (Zero [n] p5 _)))))
   956  	&& isConstZero(x)
   957  	&& o1 >= 0 && t1.Size() + o1 <= n && isSamePtr(p1, p5)
   958  	&& disjoint(op, t1.Size(), p2, t2.Size())
   959  	&& disjoint(op, t1.Size(), p3, t3.Size())
   960  	&& disjoint(op, t1.Size(), p4, t4.Size())
   961  	=> mem
   962  
   963  // Collapse OffPtr
   964  (OffPtr (OffPtr p [y]) [x]) => (OffPtr p [x+y])
   965  (OffPtr p [0]) && v.Type.Compare(p.Type) == types.CMPeq => p
   966  
   967  // indexing operations
   968  // Note: bounds check has already been done
   969  (PtrIndex <t> ptr idx) && config.PtrSize == 4 && is32Bit(t.Elem().Size()) => (AddPtr ptr (Mul32 <typ.Int> idx (Const32 <typ.Int> [int32(t.Elem().Size())])))
   970  (PtrIndex <t> ptr idx) && config.PtrSize == 8 => (AddPtr ptr (Mul64 <typ.Int> idx (Const64 <typ.Int> [t.Elem().Size()])))
   971  
   972  // struct operations
   973  (StructSelect [i] x:(StructMake ___)) => x.Args[i]
   974  (Load <t> _ _) && t.IsStruct() && t.Size() > 0 && CanSSA(t) && !t.IsSIMD() => rewriteStructLoad(v)
   975  (Store _ (StructMake ___) _) => rewriteStructStore(v)
   976  
   977  (StructSelect [i] x:(Load <t> ptr mem)) && !CanSSA(t) =>
   978    @x.Block (Load <v.Type> (OffPtr <v.Type.PtrTo()> [t.FieldOff(int(i))] ptr) mem)
   979  
   980  // Putting struct{*byte} and similar into direct interfaces.
   981  (IMake _typ (StructMake ___)) => imakeOfStructMake(v)
   982  (StructSelect (IData x)) && v.Type.Size() > 0 => (IData x)
   983  (StructSelect (IData x)) && v.Type.Size() == 0 => (Empty)
   984  
   985  // un-SSAable values use mem->mem copies
   986  (Store {t} dst (Load src mem) mem) && !CanSSA(t) =>
   987  	(Move {t} [t.Size()] dst src mem)
   988  (Store {t} dst (Load src mem) (VarDef {x} mem)) && !CanSSA(t) =>
   989  	(Move {t} [t.Size()] dst src (VarDef {x} mem))
   990  
   991  // array ops
   992  (ArraySelect (ArrayMake1 x)) => x
   993  
   994  (Load <t> ptr mem) && t.IsArray() && t.NumElem() == 1 && CanSSA(t) =>
   995    (ArrayMake1 (Load <t.Elem()> ptr mem))
   996  
   997  (Store dst (ArrayMake1 e) mem) => (Store {e.Type} dst e mem)
   998  
   999  // Putting [1]*byte and similar into direct interfaces.
  1000  (IMake _typ (ArrayMake1 val)) => (IMake _typ val)
  1001  (ArraySelect [0] (IData x)) => (IData x)
  1002  
  1003  // zero-sized values.
  1004  (Load <t> _ _) && t.Size() == 0 => (Empty)
  1005  (Store _ (Empty) mem) => mem
  1006  
  1007  // string ops
  1008  // Decomposing StringMake and lowering of StringPtr and StringLen
  1009  // happens in a later pass, dec, so that these operations are available
  1010  // to other passes for optimizations.
  1011  (StringPtr (StringMake (Addr <t> {s} base) _)) => (Addr <t> {s} base)
  1012  (StringLen (StringMake _ (Const64 <t> [c]))) => (Const64 <t> [c])
  1013  (ConstString {str}) && config.PtrSize == 4 && str == "" =>
  1014    (StringMake (ConstNil) (Const32 <typ.Int> [0]))
  1015  (ConstString {str}) && config.PtrSize == 8 && str == "" =>
  1016    (StringMake (ConstNil) (Const64 <typ.Int> [0]))
  1017  (ConstString {str}) && config.PtrSize == 4 && str != "" =>
  1018    (StringMake
  1019      (Addr <typ.BytePtr> {fe.StringData(str)}
  1020        (SB))
  1021      (Const32 <typ.Int> [int32(len(str))]))
  1022  (ConstString {str}) && config.PtrSize == 8 && str != "" =>
  1023    (StringMake
  1024      (Addr <typ.BytePtr> {fe.StringData(str)}
  1025        (SB))
  1026      (Const64 <typ.Int> [int64(len(str))]))
  1027  
  1028  // slice ops
  1029  // Only a few slice rules are provided here.  See dec.rules for
  1030  // a more comprehensive set.
  1031  (SliceLen (SliceMake _ (Const64 <t> [c]) _)) => (Const64 <t> [c])
  1032  (SliceCap (SliceMake _ _ (Const64 <t> [c]))) => (Const64 <t> [c])
  1033  (SliceLen (SliceMake _ (Const32 <t> [c]) _)) => (Const32 <t> [c])
  1034  (SliceCap (SliceMake _ _ (Const32 <t> [c]))) => (Const32 <t> [c])
  1035  (SlicePtr (SliceMake (SlicePtr x) _ _)) => (SlicePtr x)
  1036  (SliceLen (SliceMake _ (SliceLen x) _)) => (SliceLen x)
  1037  (SliceCap (SliceMake _ _ (SliceCap x))) => (SliceCap x)
  1038  (SliceCap (SliceMake _ _ (SliceLen x))) => (SliceLen x)
  1039  (ConstSlice) && config.PtrSize == 4 =>
  1040    (SliceMake
  1041      (ConstNil <v.Type.Elem().PtrTo()>)
  1042      (Const32 <typ.Int> [0])
  1043      (Const32 <typ.Int> [0]))
  1044  (ConstSlice) && config.PtrSize == 8 =>
  1045    (SliceMake
  1046      (ConstNil <v.Type.Elem().PtrTo()>)
  1047      (Const64 <typ.Int> [0])
  1048      (Const64 <typ.Int> [0]))
  1049  (SliceLen (Phi (SliceMake _ x _) (SliceMake _ x _))) => x
  1050  (SliceCap (Phi (SliceMake _ _ x) (SliceMake _ _ x))) => x
  1051  
  1052  // Special rule to help constant slicing; len > 0 implies cap > 0 implies Slicemask is all 1
  1053  (SliceMake (AddPtr <t> x (And64 y (Slicemask _))) w:(Const64 [c]) z) && c > 0 => (SliceMake (AddPtr <t> x y) w z)
  1054  (SliceMake (AddPtr <t> x (And32 y (Slicemask _))) w:(Const32 [c]) z) && c > 0 => (SliceMake (AddPtr <t> x y) w z)
  1055  
  1056  // interface ops
  1057  (ConstInterface) =>
  1058    (IMake
  1059      (ConstNil <typ.Uintptr>)
  1060      (ConstNil <typ.BytePtr>))
  1061  
  1062  (NilCheck ptr:(GetG mem) mem) => ptr
  1063  
  1064  (If (Not cond) yes no) => (If cond no yes)
  1065  (If (ConstBool [c]) yes no) && c => (First yes no)
  1066  (If (ConstBool [c]) yes no) && !c => (First no yes)
  1067  
  1068  (Phi <t> nx:(Not x) ny:(Not y)) && nx.Uses == 1 && ny.Uses == 1 => (Not (Phi <t> x y))
  1069  
  1070  // Get rid of Convert ops for pointer arithmetic on unsafe.Pointer.
  1071  (Convert (Add(64|32) (Convert ptr mem) off) mem) => (AddPtr ptr off)
  1072  (Convert (Convert ptr mem) mem) => ptr
  1073  // Note: it is important that the target rewrite is ptr+(off1+off2), not (ptr+off1)+off2.
  1074  // We must ensure that no intermediate computations are invalid pointers.
  1075  (Convert a:(Add(64|32) (Add(64|32) (Convert ptr mem) off1) off2) mem) => (AddPtr ptr (Add(64|32) <a.Type> off1 off2))
  1076  
  1077  // Simplification of divisions.
  1078  // Only trivial, easily analyzed (by prove) rewrites here.
  1079  // Strength reduction of div to mul is delayed to divmod.rules.
  1080  
  1081  // Signed divide by a negative constant.  Rewrite to divide by a positive constant.
  1082  (Div8  <t> n (Const8  [c])) && c < 0 && c != -1<<7  => (Neg8  (Div8  <t> n (Const8  <t> [-c])))
  1083  (Div16 <t> n (Const16 [c])) && c < 0 && c != -1<<15 => (Neg16 (Div16 <t> n (Const16 <t> [-c])))
  1084  (Div32 <t> n (Const32 [c])) && c < 0 && c != -1<<31 => (Neg32 (Div32 <t> n (Const32 <t> [-c])))
  1085  (Div64 <t> n (Const64 [c])) && c < 0 && c != -1<<63 => (Neg64 (Div64 <t> n (Const64 <t> [-c])))
  1086  
  1087  // Dividing by the most-negative number.  Result is always 0 except
  1088  // if the input is also the most-negative number.
  1089  // We can detect that using the sign bit of x & -x.
  1090  (Div64 x (Const64 [-1<<63])) && isNonNegative(x) => (Const64 [0])
  1091  (Div8  <t> x (Const8  [-1<<7 ])) => (Rsh8Ux64  (And8  <t> x (Neg8  <t> x)) (Const64 <typ.UInt64> [7 ]))
  1092  (Div16 <t> x (Const16 [-1<<15])) => (Rsh16Ux64 (And16 <t> x (Neg16 <t> x)) (Const64 <typ.UInt64> [15]))
  1093  (Div32 <t> x (Const32 [-1<<31])) => (Rsh32Ux64 (And32 <t> x (Neg32 <t> x)) (Const64 <typ.UInt64> [31]))
  1094  (Div64 <t> x (Const64 [-1<<63])) => (Rsh64Ux64 (And64 <t> x (Neg64 <t> x)) (Const64 <typ.UInt64> [63]))
  1095  
  1096  // Unsigned divide by power of 2.  Strength reduce to a shift.
  1097  (Div8u  n (Const8  [c])) && isPowerOfTwo(uint8(c)) => (Rsh8Ux64  n (Const64 <typ.UInt64> [log8u(uint8(c))]))
  1098  (Div16u n (Const16 [c])) && isPowerOfTwo(uint16(c)) => (Rsh16Ux64 n (Const64 <typ.UInt64> [log16u(uint16(c))]))
  1099  (Div32u n (Const32 [c])) && isPowerOfTwo(uint32(c)) => (Rsh32Ux64 n (Const64 <typ.UInt64> [log32u(uint32(c))]))
  1100  (Div64u n (Const64 [c])) && isPowerOfTwo(uint64(c)) => (Rsh64Ux64 n (Const64 <typ.UInt64> [log64u(uint64(c))]))
  1101  
  1102  // Strength reduce multiplication by a power of two to a shift.
  1103  // Excluded from early opt so that prove can recognize mod
  1104  // by the x - (x/d)*d pattern.
  1105  // (Runs during "middle opt" and "late opt".)
  1106  (Mul8  <t> x (Const8  [c])) && isPowerOfTwo(uint8(c)) && v.Block.Func.pass.name != "opt" =>
  1107    (Lsh8x64  <t> x (Const64 <typ.UInt64> [log8u(uint8(c))]))
  1108  (Mul16 <t> x (Const16 [c])) && isPowerOfTwo(uint16(c)) && v.Block.Func.pass.name != "opt" =>
  1109    (Lsh16x64 <t> x (Const64 <typ.UInt64> [log16u(uint16(c))]))
  1110  (Mul32 <t> x (Const32 [c])) && isPowerOfTwo(uint32(c)) && v.Block.Func.pass.name != "opt" =>
  1111    (Lsh32x64 <t> x (Const64 <typ.UInt64> [log32u(uint32(c))]))
  1112  (Mul64 <t> x (Const64 [c])) && isPowerOfTwo(uint64(c)) && v.Block.Func.pass.name != "opt" =>
  1113    (Lsh64x64 <t> x (Const64 <typ.UInt64> [log64u(uint64(c))]))
  1114  (Mul8  <t> x (Const8  [c])) && isPowerOfTwo(uint8(-c)) && v.Block.Func.pass.name != "opt" =>
  1115    (Neg8  (Lsh8x64  <t> x (Const64 <typ.UInt64> [log8u(uint8(-c))])))
  1116  (Mul16 <t> x (Const16 [c])) && isPowerOfTwo(uint16(-c)) && v.Block.Func.pass.name != "opt" =>
  1117    (Neg16 (Lsh16x64 <t> x (Const64 <typ.UInt64> [log16u(uint16(-c))])))
  1118  (Mul32 <t> x (Const32 [c])) && isPowerOfTwo(uint32(-c)) && v.Block.Func.pass.name != "opt" =>
  1119    (Neg32 (Lsh32x64 <t> x (Const64 <typ.UInt64> [log32u(uint32(-c))])))
  1120  (Mul64 <t> x (Const64 [c])) && isPowerOfTwo(uint64(-c)) && v.Block.Func.pass.name != "opt" =>
  1121    (Neg64 (Lsh64x64 <t> x (Const64 <typ.UInt64> [log64u(uint64(-c))])))
  1122  
  1123  // Strength reduction of mod to div.
  1124  // Strength reduction of div to mul is delayed to divmod.rules.
  1125  
  1126  // Unsigned mod by power of 2 constant.
  1127  (Mod8u  <t> n (Const8  [c])) && isPowerOfTwo(uint8(c)) => (And8  n (Const8  <t> [c-1]))
  1128  (Mod16u <t> n (Const16 [c])) && isPowerOfTwo(uint16(c)) => (And16 n (Const16 <t> [c-1]))
  1129  (Mod32u <t> n (Const32 [c])) && isPowerOfTwo(uint32(c)) => (And32 n (Const32 <t> [c-1]))
  1130  (Mod64u <t> n (Const64 [c])) && isPowerOfTwo(uint64(c)) => (And64 n (Const64 <t> [c-1]))
  1131  
  1132  // Signed non-negative mod by power of 2 constant.
  1133  // TODO: Replace ModN with ModNu in prove.
  1134  (Mod8  <t> n (Const8  [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And8  n (Const8  <t> [c-1]))
  1135  (Mod16 <t> n (Const16 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And16 n (Const16 <t> [c-1]))
  1136  (Mod32 <t> n (Const32 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And32 n (Const32 <t> [c-1]))
  1137  (Mod64 <t> n (Const64 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And64 n (Const64 <t> [c-1]))
  1138  (Mod64 n (Const64 [-1<<63])) && isNonNegative(n)                   => n
  1139  
  1140  // Signed mod by negative constant.
  1141  (Mod8  <t> n (Const8  [c])) && c < 0 && c != -1<<7  => (Mod8  <t> n (Const8  <t> [-c]))
  1142  (Mod16 <t> n (Const16 [c])) && c < 0 && c != -1<<15 => (Mod16 <t> n (Const16 <t> [-c]))
  1143  (Mod32 <t> n (Const32 [c])) && c < 0 && c != -1<<31 => (Mod32 <t> n (Const32 <t> [-c]))
  1144  (Mod64 <t> n (Const64 [c])) && c < 0 && c != -1<<63 => (Mod64 <t> n (Const64 <t> [-c]))
  1145  
  1146  // All other mods by constants, do A%B = A-(A/B*B).
  1147  // This implements % with two * and a bunch of ancillary ops.
  1148  // One of the * is free if the user's code also computes A/B.
  1149  (Mod8   <t> x (Const8  [c])) && x.Op != OpConst8  && (c > 0 || c == -1<<7)
  1150    => (Sub8  x (Mul8  <t> (Div8   <t> x (Const8  <t> [c])) (Const8  <t> [c])))
  1151  (Mod16  <t> x (Const16 [c])) && x.Op != OpConst16 && (c > 0 || c == -1<<15)
  1152    => (Sub16 x (Mul16 <t> (Div16  <t> x (Const16 <t> [c])) (Const16 <t> [c])))
  1153  (Mod32  <t> x (Const32 [c])) && x.Op != OpConst32 && (c > 0 || c == -1<<31)
  1154    => (Sub32 x (Mul32 <t> (Div32  <t> x (Const32 <t> [c])) (Const32 <t> [c])))
  1155  (Mod64  <t> x (Const64 [c])) && x.Op != OpConst64 && (c > 0 || c == -1<<63)
  1156    => (Sub64 x (Mul64 <t> (Div64  <t> x (Const64 <t> [c])) (Const64 <t> [c])))
  1157  (Mod8u  <t> x (Const8  [c])) && x.Op != OpConst8  && c != 0
  1158    => (Sub8  x (Mul8  <t> (Div8u  <t> x (Const8  <t> [c])) (Const8  <t> [c])))
  1159  (Mod16u <t> x (Const16 [c])) && x.Op != OpConst16 && c != 0
  1160    => (Sub16 x (Mul16 <t> (Div16u <t> x (Const16 <t> [c])) (Const16 <t> [c])))
  1161  (Mod32u <t> x (Const32 [c])) && x.Op != OpConst32 && c != 0
  1162    => (Sub32 x (Mul32 <t> (Div32u <t> x (Const32 <t> [c])) (Const32 <t> [c])))
  1163  (Mod64u <t> x (Const64 [c])) && x.Op != OpConst64 && c != 0
  1164    => (Sub64 x (Mul64 <t> (Div64u <t> x (Const64 <t> [c])) (Const64 <t> [c])))
  1165  
  1166  // Set up for mod->mul+rot optimization in genericlateopt.rules.
  1167  // For architectures without rotates on less than 32-bits, promote to 32-bit.
  1168  // TODO: Also != 0 case?
  1169  (Eq8 (Mod8u x (Const8  [c])) (Const8 [0])) && x.Op != OpConst8 && udivisibleOK8(c) && !hasSmallRotate(config) =>
  1170  	(Eq32 (Mod32u <typ.UInt32> (ZeroExt8to32 <typ.UInt32> x) (Const32 <typ.UInt32> [int32(uint8(c))])) (Const32 <typ.UInt32> [0]))
  1171  (Eq16 (Mod16u x (Const16  [c])) (Const16 [0])) && x.Op != OpConst16 && udivisibleOK16(c) && !hasSmallRotate(config) =>
  1172  	(Eq32 (Mod32u <typ.UInt32> (ZeroExt16to32 <typ.UInt32> x) (Const32 <typ.UInt32> [int32(uint16(c))])) (Const32 <typ.UInt32> [0]))
  1173  (Eq8 (Mod8 x (Const8  [c])) (Const8 [0])) && x.Op != OpConst8 && sdivisibleOK8(c) && !hasSmallRotate(config) =>
  1174  	(Eq32 (Mod32 <typ.Int32> (SignExt8to32 <typ.Int32> x) (Const32 <typ.Int32> [int32(c)])) (Const32 <typ.Int32> [0]))
  1175  (Eq16 (Mod16 x (Const16  [c])) (Const16 [0])) && x.Op != OpConst16 && sdivisibleOK16(c) && !hasSmallRotate(config) =>
  1176  	(Eq32 (Mod32 <typ.Int32> (SignExt16to32 <typ.Int32> x) (Const32 <typ.Int32> [int32(c)])) (Const32 <typ.Int32> [0]))
  1177  
  1178  (Eq(8|16|32|64)  s:(Sub(8|16|32|64) x y) (Const(8|16|32|64) [0])) && s.Uses == 1 => (Eq(8|16|32|64)  x y)
  1179  (Neq(8|16|32|64) s:(Sub(8|16|32|64) x y) (Const(8|16|32|64) [0])) && s.Uses == 1 => (Neq(8|16|32|64) x y)
  1180  
  1181  // Optimize bitsets
  1182  (Eq(8|16|32|64) (And(8|16|32|64) <t> x (Const(8|16|32|64) <t> [y])) (Const(8|16|32|64) <t> [y])) && oneBit(y)
  1183    => (Neq(8|16|32|64) (And(8|16|32|64) <t> x (Const(8|16|32|64) <t> [y])) (Const(8|16|32|64) <t> [0]))
  1184  (Neq(8|16|32|64) (And(8|16|32|64) <t> x (Const(8|16|32|64) <t> [y])) (Const(8|16|32|64) <t> [y])) && oneBit(y)
  1185    => (Eq(8|16|32|64) (And(8|16|32|64) <t> x (Const(8|16|32|64) <t> [y])) (Const(8|16|32|64) <t> [0]))
  1186  
  1187  // Mark newly generated bounded shifts as bounded, for opt passes after prove.
  1188  (Lsh64x(8|16|32|64)  [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 64 => (Lsh64x(8|16|32|64)  [true] x con)
  1189  (Rsh64x(8|16|32|64)  [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 64 => (Rsh64x(8|16|32|64)  [true] x con)
  1190  (Rsh64Ux(8|16|32|64) [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 64 => (Rsh64Ux(8|16|32|64) [true] x con)
  1191  (Lsh32x(8|16|32|64)  [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 32 => (Lsh32x(8|16|32|64)  [true] x con)
  1192  (Rsh32x(8|16|32|64)  [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 32 => (Rsh32x(8|16|32|64)  [true] x con)
  1193  (Rsh32Ux(8|16|32|64) [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 32 => (Rsh32Ux(8|16|32|64) [true] x con)
  1194  (Lsh16x(8|16|32|64)  [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 16 => (Lsh16x(8|16|32|64)  [true] x con)
  1195  (Rsh16x(8|16|32|64)  [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 16 => (Rsh16x(8|16|32|64)  [true] x con)
  1196  (Rsh16Ux(8|16|32|64) [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 16 => (Rsh16Ux(8|16|32|64) [true] x con)
  1197  (Lsh8x(8|16|32|64)   [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 8  => (Lsh8x(8|16|32|64)   [true] x con)
  1198  (Rsh8x(8|16|32|64)   [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 8  => (Rsh8x(8|16|32|64)   [true] x con)
  1199  (Rsh8Ux(8|16|32|64)  [false] x con:(Const(8|16|32|64) [c])) && 0 < c && c < 8  => (Rsh8Ux(8|16|32|64)  [true] x con)
  1200  
  1201  // Reassociate expressions involving
  1202  // constants such that constants come first,
  1203  // exposing obvious constant-folding opportunities.
  1204  // Reassociate (op (op y C) x) to (op C (op x y)) or similar, where C
  1205  // is constant, which pushes constants to the outside
  1206  // of the expression. At that point, any constant-folding
  1207  // opportunities should be obvious.
  1208  // Note: don't include AddPtr here! In order to maintain the
  1209  // invariant that pointers must stay within the pointed-to object,
  1210  // we can't pull part of a pointer computation above the AddPtr.
  1211  // See issue 37881.
  1212  // Note: we don't need to handle any (x-C) cases because we already rewrite
  1213  // (x-C) to (x+(-C)).
  1214  
  1215  // x + (C + z) -> C + (x + z)
  1216  (Add64 (Add64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Add64 i (Add64 <t> z x))
  1217  (Add32 (Add32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Add32 i (Add32 <t> z x))
  1218  (Add16 (Add16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Add16 i (Add16 <t> z x))
  1219  (Add8  (Add8  i:(Const8  <t>) z) x) && (z.Op != OpConst8  && x.Op != OpConst8)  => (Add8  i (Add8  <t> z x))
  1220  
  1221  // x + (C - z) -> C + (x - z)
  1222  (Add64 (Sub64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Add64 i (Sub64 <t> x z))
  1223  (Add32 (Sub32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Add32 i (Sub32 <t> x z))
  1224  (Add16 (Sub16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Add16 i (Sub16 <t> x z))
  1225  (Add8  (Sub8  i:(Const8  <t>) z) x) && (z.Op != OpConst8  && x.Op != OpConst8)  => (Add8  i (Sub8  <t> x z))
  1226  
  1227  // x - (C - z) -> x + (z - C) -> (x + z) - C
  1228  (Sub64 x (Sub64 i:(Const64 <t>) z)) && (z.Op != OpConst64 && x.Op != OpConst64) => (Sub64 (Add64 <t> x z) i)
  1229  (Sub32 x (Sub32 i:(Const32 <t>) z)) && (z.Op != OpConst32 && x.Op != OpConst32) => (Sub32 (Add32 <t> x z) i)
  1230  (Sub16 x (Sub16 i:(Const16 <t>) z)) && (z.Op != OpConst16 && x.Op != OpConst16) => (Sub16 (Add16 <t> x z) i)
  1231  (Sub8  x (Sub8  i:(Const8  <t>) z)) && (z.Op != OpConst8  && x.Op != OpConst8)  => (Sub8  (Add8  <t> x z) i)
  1232  
  1233  // x - (z + C) -> x + (-z - C) -> (x - z) - C
  1234  (Sub64 x (Add64 z i:(Const64 <t>))) && (z.Op != OpConst64 && x.Op != OpConst64) => (Sub64 (Sub64 <t> x z) i)
  1235  (Sub32 x (Add32 z i:(Const32 <t>))) && (z.Op != OpConst32 && x.Op != OpConst32) => (Sub32 (Sub32 <t> x z) i)
  1236  (Sub16 x (Add16 z i:(Const16 <t>))) && (z.Op != OpConst16 && x.Op != OpConst16) => (Sub16 (Sub16 <t> x z) i)
  1237  (Sub8  x (Add8  z i:(Const8  <t>))) && (z.Op != OpConst8  && x.Op != OpConst8)  => (Sub8 (Sub8  <t> x z) i)
  1238  
  1239  // (C - z) - x -> C - (z + x)
  1240  (Sub64 (Sub64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Sub64 i (Add64 <t> z x))
  1241  (Sub32 (Sub32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Sub32 i (Add32 <t> z x))
  1242  (Sub16 (Sub16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Sub16 i (Add16 <t> z x))
  1243  (Sub8  (Sub8  i:(Const8  <t>) z) x) && (z.Op != OpConst8  && x.Op != OpConst8)  => (Sub8  i (Add8  <t> z x))
  1244  
  1245  // (z + C) -x -> C + (z - x)
  1246  (Sub64 (Add64 z i:(Const64 <t>)) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Add64 i (Sub64 <t> z x))
  1247  (Sub32 (Add32 z i:(Const32 <t>)) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Add32 i (Sub32 <t> z x))
  1248  (Sub16 (Add16 z i:(Const16 <t>)) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Add16 i (Sub16 <t> z x))
  1249  (Sub8  (Add8  z i:(Const8  <t>)) x) && (z.Op != OpConst8  && x.Op != OpConst8)  => (Add8  i (Sub8  <t> z x))
  1250  
  1251  // x & (C & z) -> C & (x & z)
  1252  (And64 (And64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (And64 i (And64 <t> z x))
  1253  (And32 (And32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (And32 i (And32 <t> z x))
  1254  (And16 (And16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (And16 i (And16 <t> z x))
  1255  (And8  (And8  i:(Const8  <t>) z) x) && (z.Op != OpConst8  && x.Op != OpConst8)  => (And8  i (And8  <t> z x))
  1256  
  1257  // x | (C | z) -> C | (x | z)
  1258  (Or64 (Or64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Or64 i (Or64 <t> z x))
  1259  (Or32 (Or32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Or32 i (Or32 <t> z x))
  1260  (Or16 (Or16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Or16 i (Or16 <t> z x))
  1261  (Or8  (Or8  i:(Const8  <t>) z) x) && (z.Op != OpConst8  && x.Op != OpConst8)  => (Or8  i (Or8  <t> z x))
  1262  
  1263  // x ^ (C ^ z) -> C ^ (x ^ z)
  1264  (Xor64 (Xor64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Xor64 i (Xor64 <t> z x))
  1265  (Xor32 (Xor32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Xor32 i (Xor32 <t> z x))
  1266  (Xor16 (Xor16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Xor16 i (Xor16 <t> z x))
  1267  (Xor8  (Xor8  i:(Const8  <t>) z) x) && (z.Op != OpConst8  && x.Op != OpConst8)  => (Xor8  i (Xor8  <t> z x))
  1268  
  1269  // x * (D * z) = D * (x * z)
  1270  (Mul64 (Mul64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Mul64 i (Mul64 <t> x z))
  1271  (Mul32 (Mul32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Mul32 i (Mul32 <t> x z))
  1272  (Mul16 (Mul16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Mul16 i (Mul16 <t> x z))
  1273  (Mul8  (Mul8  i:(Const8  <t>) z) x) && (z.Op != OpConst8  && x.Op != OpConst8)  => (Mul8  i (Mul8  <t> x z))
  1274  
  1275  // C + (D + x) -> (C + D) + x
  1276  (Add64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) => (Add64 (Const64 <t> [c+d]) x)
  1277  (Add32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) => (Add32 (Const32 <t> [c+d]) x)
  1278  (Add16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) => (Add16 (Const16 <t> [c+d]) x)
  1279  (Add8  (Const8  <t> [c]) (Add8  (Const8  <t> [d]) x)) => (Add8  (Const8  <t> [c+d]) x)
  1280  
  1281  // C + (D - x) -> (C + D) - x
  1282  (Add64 (Const64 <t> [c]) (Sub64 (Const64 <t> [d]) x)) => (Sub64 (Const64 <t> [c+d]) x)
  1283  (Add32 (Const32 <t> [c]) (Sub32 (Const32 <t> [d]) x)) => (Sub32 (Const32 <t> [c+d]) x)
  1284  (Add16 (Const16 <t> [c]) (Sub16 (Const16 <t> [d]) x)) => (Sub16 (Const16 <t> [c+d]) x)
  1285  (Add8  (Const8  <t> [c]) (Sub8  (Const8  <t> [d]) x)) => (Sub8  (Const8  <t> [c+d]) x)
  1286  
  1287  // C - (D - x) -> (C - D) + x
  1288  (Sub64 (Const64 <t> [c]) (Sub64 (Const64 <t> [d]) x)) => (Add64 (Const64 <t> [c-d]) x)
  1289  (Sub32 (Const32 <t> [c]) (Sub32 (Const32 <t> [d]) x)) => (Add32 (Const32 <t> [c-d]) x)
  1290  (Sub16 (Const16 <t> [c]) (Sub16 (Const16 <t> [d]) x)) => (Add16 (Const16 <t> [c-d]) x)
  1291  (Sub8  (Const8  <t> [c]) (Sub8  (Const8  <t> [d]) x)) => (Add8  (Const8  <t> [c-d]) x)
  1292  
  1293  // C - (D + x) -> (C - D) - x
  1294  (Sub64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) => (Sub64 (Const64 <t> [c-d]) x)
  1295  (Sub32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) => (Sub32 (Const32 <t> [c-d]) x)
  1296  (Sub16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) => (Sub16 (Const16 <t> [c-d]) x)
  1297  (Sub8  (Const8  <t> [c]) (Add8  (Const8  <t> [d]) x)) => (Sub8  (Const8  <t> [c-d]) x)
  1298  
  1299  // C & (D & x) -> (C & D) & x
  1300  (And64 (Const64 <t> [c]) (And64 (Const64 <t> [d]) x)) => (And64 (Const64 <t> [c&d]) x)
  1301  (And32 (Const32 <t> [c]) (And32 (Const32 <t> [d]) x)) => (And32 (Const32 <t> [c&d]) x)
  1302  (And16 (Const16 <t> [c]) (And16 (Const16 <t> [d]) x)) => (And16 (Const16 <t> [c&d]) x)
  1303  (And8  (Const8  <t> [c]) (And8  (Const8  <t> [d]) x)) => (And8  (Const8  <t> [c&d]) x)
  1304  
  1305  // C | (D | x) -> (C | D) | x
  1306  (Or64 (Const64 <t> [c]) (Or64 (Const64 <t> [d]) x)) => (Or64 (Const64 <t> [c|d]) x)
  1307  (Or32 (Const32 <t> [c]) (Or32 (Const32 <t> [d]) x)) => (Or32 (Const32 <t> [c|d]) x)
  1308  (Or16 (Const16 <t> [c]) (Or16 (Const16 <t> [d]) x)) => (Or16 (Const16 <t> [c|d]) x)
  1309  (Or8  (Const8  <t> [c]) (Or8  (Const8  <t> [d]) x)) => (Or8  (Const8  <t> [c|d]) x)
  1310  
  1311  // C ^ (D ^ x) -> (C ^ D) ^ x
  1312  (Xor64 (Const64 <t> [c]) (Xor64 (Const64 <t> [d]) x)) => (Xor64 (Const64 <t> [c^d]) x)
  1313  (Xor32 (Const32 <t> [c]) (Xor32 (Const32 <t> [d]) x)) => (Xor32 (Const32 <t> [c^d]) x)
  1314  (Xor16 (Const16 <t> [c]) (Xor16 (Const16 <t> [d]) x)) => (Xor16 (Const16 <t> [c^d]) x)
  1315  (Xor8  (Const8  <t> [c]) (Xor8  (Const8  <t> [d]) x)) => (Xor8  (Const8  <t> [c^d]) x)
  1316  
  1317  // C * (D * x) = (C * D) * x
  1318  (Mul64 (Const64 <t> [c]) (Mul64 (Const64 <t> [d]) x)) => (Mul64 (Const64 <t> [c*d]) x)
  1319  (Mul32 (Const32 <t> [c]) (Mul32 (Const32 <t> [d]) x)) => (Mul32 (Const32 <t> [c*d]) x)
  1320  (Mul16 (Const16 <t> [c]) (Mul16 (Const16 <t> [d]) x)) => (Mul16 (Const16 <t> [c*d]) x)
  1321  (Mul8  (Const8  <t> [c]) (Mul8  (Const8  <t> [d]) x)) => (Mul8  (Const8  <t> [c*d]) x)
  1322  
  1323  // floating point optimizations
  1324  (Mul(32|64)F x (Const(32|64)F [1])) => x
  1325  (Mul32F x (Const32F [-1])) => (Neg32F x)
  1326  (Mul64F x (Const64F [-1])) => (Neg64F x)
  1327  (Mul32F x (Const32F [2])) => (Add32F x x)
  1328  (Mul64F x (Const64F [2])) => (Add64F x x)
  1329  
  1330  (Div32F x (Const32F <t> [c])) && reciprocalExact32(c) => (Mul32F x (Const32F <t> [1/c]))
  1331  (Div64F x (Const64F <t> [c])) && reciprocalExact64(c) => (Mul64F x (Const64F <t> [1/c]))
  1332  
  1333  // rewrite single-precision sqrt expression "float32(math.Sqrt(float64(x)))"
  1334  (Cvt64Fto32F sqrt0:(Sqrt (Cvt32Fto64F x))) && sqrt0.Uses==1 => (Sqrt32 x)
  1335  
  1336  (Sqrt (Const64F [c])) && !math.IsNaN(math.Sqrt(c)) => (Const64F [math.Sqrt(c)])
  1337  
  1338  // for rewriting constant folded math/bits ops
  1339  (Select0 (MakeTuple x y)) => x
  1340  (Select1 (MakeTuple x y)) => y
  1341  
  1342  // for rewriting results of some late-expanded rewrites (below)
  1343  (SelectN [n] m:(MakeResult ___)) => m.Args[n]
  1344  
  1345  // TODO(matloob): Try out having non-zeroing mallocs for prointerless
  1346  // memory, and leaving the zeroing here. Then the compiler can remove
  1347  // the zeroing if the user has explicit writes to the whole object.
  1348  
  1349  // for late-expanded calls, recognize newobject and remove zeroing and nilchecks
  1350  (Zero (SelectN [0] call:(StaticLECall ___)) mem:(SelectN [1] call))
  1351  	&& isMalloc(call.Aux)
  1352  	=> mem
  1353  
  1354  (Store (SelectN [0] call:(StaticLECall ___)) x mem:(SelectN [1] call))
  1355  	&& isConstZero(x)
  1356  	&& isMalloc(call.Aux)
  1357  	=> mem
  1358  
  1359  (Store (OffPtr (SelectN [0] call:(StaticLECall ___))) x mem:(SelectN [1] call))
  1360  	&& isConstZero(x)
  1361  	&& isMalloc(call.Aux)
  1362  	=> mem
  1363  
  1364  (NilCheck ptr:(SelectN [0] call:(StaticLECall ___)) _)
  1365  	&& isMalloc(call.Aux)
  1366  	&& warnRule(fe.Debug_checknil(), v, "removed nil check")
  1367  	=> ptr
  1368  
  1369  (NilCheck ptr:(OffPtr (SelectN [0] call:(StaticLECall ___))) _)
  1370  	&& isMalloc(call.Aux)
  1371  	&& warnRule(fe.Debug_checknil(), v, "removed nil check")
  1372  	=> ptr
  1373  
  1374  // Addresses of globals are always non-nil.
  1375  (NilCheck          ptr:(Addr {_} (SB))    _) => ptr
  1376  (NilCheck ptr:(Convert (Addr {_} (SB)) _) _) => ptr
  1377  
  1378  // Addresses of locals are always non-nil.
  1379  (NilCheck ptr:(LocalAddr _ _) _)
  1380  	&& warnRule(fe.Debug_checknil(), v, "removed nil check")
  1381  	=> ptr
  1382  
  1383  // .dict args are always non-nil.
  1384  (NilCheck ptr:(Arg {sym}) _) && isDictArgSym(sym) => ptr
  1385  
  1386  // Nil checks of nil checks are redundant.
  1387  // See comment at the end of https://go-review.googlesource.com/c/go/+/537775.
  1388  (NilCheck ptr:(NilCheck _ _) _ ) => ptr
  1389  
  1390  // for late-expanded calls, recognize memequal applied to a single constant byte
  1391  // Support is limited by [1-8] byte sizes
  1392  (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [1]) mem)
  1393    && isSameCall(callAux, "runtime.memequal")
  1394    && symIsRO(scon)
  1395    => (MakeResult (Eq8 (Load <typ.Int8> sptr mem) (Const8 <typ.Int8> [int8(read8(scon,0))])) mem)
  1396  
  1397  (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [1]) mem)
  1398    && isSameCall(callAux, "runtime.memequal")
  1399    && symIsRO(scon)
  1400    => (MakeResult (Eq8 (Load <typ.Int8> sptr mem) (Const8 <typ.Int8> [int8(read8(scon,0))])) mem)
  1401  
  1402  (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [2]) mem)
  1403    && isSameCall(callAux, "runtime.memequal")
  1404    && symIsRO(scon)
  1405    && canLoadUnaligned(config)
  1406    => (MakeResult (Eq16 (Load <typ.Int16> sptr mem) (Const16 <typ.Int16> [int16(read16(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
  1407  
  1408  (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [2]) mem)
  1409    && isSameCall(callAux, "runtime.memequal")
  1410    && symIsRO(scon)
  1411    && canLoadUnaligned(config)
  1412    => (MakeResult (Eq16 (Load <typ.Int16> sptr mem) (Const16 <typ.Int16> [int16(read16(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
  1413  
  1414  (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [4]) mem)
  1415    && isSameCall(callAux, "runtime.memequal")
  1416    && symIsRO(scon)
  1417    && canLoadUnaligned(config)
  1418    => (MakeResult (Eq32 (Load <typ.Int32> sptr mem) (Const32 <typ.Int32> [int32(read32(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
  1419  
  1420  (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [4]) mem)
  1421    && isSameCall(callAux, "runtime.memequal")
  1422    && symIsRO(scon)
  1423    && canLoadUnaligned(config)
  1424    => (MakeResult (Eq32 (Load <typ.Int32> sptr mem) (Const32 <typ.Int32> [int32(read32(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
  1425  
  1426  (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [8]) mem)
  1427    && isSameCall(callAux, "runtime.memequal")
  1428    && symIsRO(scon)
  1429    && canLoadUnaligned(config) && config.PtrSize == 8
  1430    => (MakeResult (Eq64 (Load <typ.Int64> sptr mem) (Const64 <typ.Int64> [int64(read64(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
  1431  
  1432  (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [8]) mem)
  1433    && isSameCall(callAux, "runtime.memequal")
  1434    && symIsRO(scon)
  1435    && canLoadUnaligned(config) && config.PtrSize == 8
  1436    => (MakeResult (Eq64 (Load <typ.Int64> sptr mem) (Const64 <typ.Int64> [int64(read64(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
  1437  
  1438  (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [3]) mem)
  1439    && isSameCall(callAux, "runtime.memequal")
  1440    && symIsRO(scon)
  1441    && canLoadUnaligned(config) =>
  1442    (MakeResult
  1443      (Eq32
  1444        (Or32 <typ.Int32>
  1445          (ZeroExt16to32 <typ.Int32> (Load <typ.Int16> sptr mem))
  1446          (Lsh32x32 <typ.Int32>
  1447            (ZeroExt8to32 <typ.Int32> (Load <typ.Int8> (OffPtr <typ.BytePtr> [2] sptr) mem))
  1448            (Const32 <typ.Int32> [16])))
  1449        (Const32 <typ.Int32> [int32(uint32(read16(scon,0,config.ctxt.Arch.ByteOrder))|(uint32(read8(scon,2))<<16))]))
  1450      mem)
  1451  
  1452  (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [3]) mem)
  1453    && isSameCall(callAux, "runtime.memequal")
  1454    && symIsRO(scon)
  1455    && canLoadUnaligned(config) =>
  1456    (MakeResult
  1457      (Eq32
  1458        (Or32 <typ.Int32>
  1459          (ZeroExt16to32 <typ.Int32> (Load <typ.Int16> sptr mem))
  1460          (Lsh32x32 <typ.Int32>
  1461            (ZeroExt8to32 <typ.Int32> (Load <typ.Int8> (OffPtr <typ.BytePtr> [2] sptr) mem))
  1462            (Const32 <typ.Int32> [16])))
  1463        (Const32 <typ.Int32> [int32(uint32(read16(scon,0,config.ctxt.Arch.ByteOrder))|(uint32(read8(scon,2))<<16))]))
  1464      mem)
  1465  
  1466  (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [5]) mem)
  1467    && isSameCall(callAux, "runtime.memequal")
  1468    && symIsRO(scon)
  1469    && canLoadUnaligned(config) && config.PtrSize == 8 =>
  1470    (MakeResult
  1471      (Eq64
  1472        (Or64 <typ.Int64>
  1473          (ZeroExt32to64 <typ.Int64> (Load <typ.Int32> sptr mem))
  1474          (Lsh64x64 <typ.Int64>
  1475            (ZeroExt8to64 <typ.Int64> (Load <typ.Int8> (OffPtr <typ.BytePtr> [4] sptr) mem))
  1476            (Const64 <typ.Int64> [32])))
  1477        (Const64 <typ.Int64> [int64(uint64(read32(scon,0,config.ctxt.Arch.ByteOrder))|(uint64(read8(scon,4))<<32))]))
  1478      mem)
  1479  
  1480  (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [5]) mem)
  1481    && isSameCall(callAux, "runtime.memequal")
  1482    && symIsRO(scon)
  1483    && canLoadUnaligned(config) && config.PtrSize == 8 =>
  1484    (MakeResult
  1485      (Eq64
  1486        (Or64 <typ.Int64>
  1487          (ZeroExt32to64 <typ.Int64> (Load <typ.Int32> sptr mem))
  1488          (Lsh64x64 <typ.Int64>
  1489            (ZeroExt8to64 <typ.Int64> (Load <typ.Int8> (OffPtr <typ.BytePtr> [4] sptr) mem))
  1490            (Const64 <typ.Int64> [32])))
  1491        (Const64 <typ.Int64> [int64(uint64(read32(scon,0,config.ctxt.Arch.ByteOrder))|(uint64(read8(scon,4))<<32))]))
  1492      mem)
  1493  
  1494  (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [6]) mem)
  1495    && isSameCall(callAux, "runtime.memequal")
  1496    && symIsRO(scon)
  1497    && canLoadUnaligned(config) && config.PtrSize == 8 =>
  1498    (MakeResult
  1499      (Eq64
  1500        (Or64 <typ.Int64>
  1501          (ZeroExt32to64 <typ.Int64> (Load <typ.Int32> sptr mem))
  1502          (Lsh64x64 <typ.Int64>
  1503            (ZeroExt16to64 <typ.Int64> (Load <typ.Int16> (OffPtr <typ.BytePtr> [4] sptr) mem))
  1504            (Const64 <typ.Int64> [32])))
  1505        (Const64 <typ.Int64> [int64(uint64(read32(scon,0,config.ctxt.Arch.ByteOrder))|(uint64(read16(scon,4,config.ctxt.Arch.ByteOrder))<<32))]))
  1506      mem)
  1507  
  1508  (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [6]) mem)
  1509    && isSameCall(callAux, "runtime.memequal")
  1510    && symIsRO(scon)
  1511    && canLoadUnaligned(config) && config.PtrSize == 8 =>
  1512    (MakeResult
  1513      (Eq64
  1514        (Or64 <typ.Int64>
  1515          (ZeroExt32to64 <typ.Int64> (Load <typ.Int32> sptr mem))
  1516          (Lsh64x64 <typ.Int64>
  1517            (ZeroExt16to64 <typ.Int64> (Load <typ.Int16> (OffPtr <typ.BytePtr> [4] sptr) mem))
  1518            (Const64 <typ.Int64> [32])))
  1519        (Const64 <typ.Int64> [int64(uint64(read32(scon,0,config.ctxt.Arch.ByteOrder))|(uint64(read16(scon,4,config.ctxt.Arch.ByteOrder))<<32))]))
  1520      mem)
  1521  
  1522  (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [7]) mem)
  1523    && isSameCall(callAux, "runtime.memequal")
  1524    && symIsRO(scon)
  1525    && canLoadUnaligned(config) && config.PtrSize == 8 =>
  1526    (MakeResult
  1527      (Eq64
  1528        (Or64 <typ.Int64>
  1529          (ZeroExt32to64 <typ.Int64> (Load <typ.Int32> sptr mem))
  1530          (Lsh64x64 <typ.Int64>
  1531            (ZeroExt32to64 <typ.Int64> (Load <typ.Int32> (OffPtr <typ.BytePtr> [3] sptr) mem))
  1532            (Const64 <typ.Int64> [32])))
  1533        (Const64 <typ.Int64> [int64(uint64(read32(scon,0,config.ctxt.Arch.ByteOrder))|(uint64(read32(scon,3,config.ctxt.Arch.ByteOrder))<<32))]))
  1534      mem)
  1535  
  1536  (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [7]) mem)
  1537    && isSameCall(callAux, "runtime.memequal")
  1538    && symIsRO(scon)
  1539    && canLoadUnaligned(config) && config.PtrSize == 8 =>
  1540    (MakeResult
  1541      (Eq64
  1542        (Or64 <typ.Int64>
  1543          (ZeroExt32to64 <typ.Int64> (Load <typ.Int32> sptr mem))
  1544          (Lsh64x64 <typ.Int64>
  1545            (ZeroExt32to64 <typ.Int64> (Load <typ.Int32> (OffPtr <typ.BytePtr> [3] sptr) mem))
  1546            (Const64 <typ.Int64> [32])))
  1547        (Const64 <typ.Int64> [int64(uint64(read32(scon,0,config.ctxt.Arch.ByteOrder))|(uint64(read32(scon,3,config.ctxt.Arch.ByteOrder))<<32))]))
  1548      mem)
  1549  
  1550  (StaticLECall {callAux} _ _ (Const64 [0]) mem)
  1551    && isSameCall(callAux, "runtime.memequal")
  1552    => (MakeResult (ConstBool <typ.Bool> [true]) mem)
  1553  
  1554  (Static(Call|LECall) {callAux} p q _ mem)
  1555    && isSameCall(callAux, "runtime.memequal")
  1556    && isSamePtr(p, q)
  1557    => (MakeResult (ConstBool <typ.Bool> [true]) mem)
  1558  
  1559  (MemEq sptr tptr (Const64 [1]) mem)
  1560    => (Eq8 (Load <typ.Int8> sptr mem) (Load <typ.Int8> tptr mem))
  1561  
  1562  (Load <typ.Int8> sptr:(Addr {scon} (SB)) mem)
  1563    && symIsRO(scon)
  1564    => (Const8 <typ.Int8> [int8(read8(scon,0))])
  1565  
  1566  (MemEq sptr tptr (Const64 [2]) mem)
  1567    && canLoadUnaligned(config)
  1568    => (Eq16 (Load <typ.Int16> sptr mem) (Load <typ.Int16> tptr mem))
  1569  
  1570  (Load <typ.Int16> sptr:(Addr {scon} (SB)) mem)
  1571    && symIsRO(scon)
  1572    => (Const16 <typ.Int16> [int16(read16(scon,0,config.ctxt.Arch.ByteOrder))])
  1573  
  1574  (MemEq sptr tptr (Const64 [4]) mem)
  1575    && canLoadUnaligned(config)
  1576    => (Eq32 (Load <typ.Int32> sptr mem) (Load <typ.Int32> tptr mem))
  1577  
  1578  (Load <typ.Int32> sptr:(Addr {scon} (SB)) mem)
  1579    && symIsRO(scon)
  1580    => (Const32 <typ.Int32> [int32(read32(scon,0,config.ctxt.Arch.ByteOrder))])
  1581  
  1582  (MemEq sptr tptr (Const64 [8]) mem)
  1583    && canLoadUnaligned(config) && config.PtrSize == 8
  1584    => (Eq64 (Load <typ.Int64> sptr mem) (Load <typ.Int64> tptr mem))
  1585  
  1586  (Load <typ.Int64> sptr:(Addr {scon} (SB)) mem)
  1587    && symIsRO(scon)
  1588    => (Const64 <typ.Int64> [int64(read64(scon,0,config.ctxt.Arch.ByteOrder))])
  1589  
  1590  (MemEq _ _ (Const64 [0]) _) => (ConstBool <typ.Bool> [true])
  1591  
  1592  (MemEq p q _ _) && isSamePtr(p, q) => (ConstBool <typ.Bool> [true])
  1593  
  1594  // 3-32 bytes memeq (enabled only with support of unaligned loads and 8-byte max word size)
  1595  
  1596  (MemEq p q (Const64 [c]) mem)
  1597    && (c == 3 || c == 5 || c == 9 || c == 17)
  1598    && canLoadUnaligned(config)
  1599    && config.RegSize == 8
  1600    => (AndB (MemEq p q (Const64 <typ.Int64> [c-1]) mem)
  1601             (Eq8 (Load <typ.Int8> (OffPtr <p.Type> p [c-1]) mem) (Load <typ.Int8> (OffPtr <q.Type> q [c-1]) mem)))
  1602  
  1603  (MemEq p q (Const64 [c]) mem)
  1604    && (c == 6 || c == 10 || c == 18)
  1605    && canLoadUnaligned(config)
  1606    && config.RegSize == 8
  1607    => (AndB (MemEq p q (Const64 <typ.Int64> [c-2]) mem)
  1608             (Eq16 (Load <typ.Int16> (OffPtr <p.Type> p [c-2]) mem) (Load <typ.Int16> (OffPtr <q.Type> q [c-2]) mem)))
  1609  
  1610  (MemEq p q (Const64 [c]) mem)
  1611    && (c == 7 || c == 11 || c == 19 || c == 20)
  1612    && canLoadUnaligned(config)
  1613    && config.RegSize == 8
  1614    => (AndB (MemEq p q (Const64 <typ.Int64> [min(c-3,16)]) mem)
  1615             (Eq32 (Load <typ.Int32> (OffPtr <p.Type> p [c-4]) mem) (Load <typ.Int32> (OffPtr <q.Type> q [c-4]) mem)))
  1616  
  1617  (MemEq p q (Const64 [c]) mem)
  1618    && ((c >= 12 && c <= 16) || (c >= 21 && c <= 24))
  1619    && canLoadUnaligned(config)
  1620    && config.RegSize == 8
  1621    => (AndB (MemEq p q (Const64 <typ.Int64> [8 + int64(bool2int(c>16))*8]) mem)
  1622             (Eq64 (Load <typ.Int64> (OffPtr <p.Type> p [c-8]) mem) (Load <typ.Int64> (OffPtr <q.Type> q [c-8]) mem)))
  1623  
  1624  (MemEq p q (Const64 [c]) mem)
  1625    && c >= 25 && c <= 32
  1626    && canLoadUnaligned(config)
  1627    && config.RegSize == 8
  1628    => (AndB (MemEq p q (Const64 <typ.Int64> [16]) mem)
  1629             (MemEq (OffPtr <p.Type> p [16]) (OffPtr <q.Type> q [16]) (Const64 <typ.Int64> [c-16]) mem))
  1630  
  1631  // Turn known-size calls to memclrNoHeapPointers into a Zero.
  1632  // Note that we are using types.Types[types.TUINT8] instead of sptr.Type.Elem() - see issue 55122 and CL 431496 for more details.
  1633  (SelectN [0] call:(StaticCall {sym} sptr (Const(64|32) [c]) mem))
  1634    && isInlinableMemclr(config, int64(c))
  1635    && isSameCall(sym, "runtime.memclrNoHeapPointers")
  1636    && call.Uses == 1
  1637    && clobber(call)
  1638    => (Zero {types.Types[types.TUINT8]} [int64(c)] sptr mem)
  1639  
  1640  // Recognise make([]T, 0) and replace it with a pointer to the zerobase
  1641  (StaticLECall {callAux} _ (Const(64|32) [0]) (Const(64|32) [0]) mem)
  1642  	&& isSameCall(callAux, "runtime.makeslice")
  1643  	=> (MakeResult (Addr <v.Type.FieldType(0)> {ir.Syms.Zerobase} (SB)) mem)
  1644  
  1645  // Evaluate constant address comparisons.
  1646  (EqPtr  x x) => (ConstBool [true])
  1647  (NeqPtr x x) => (ConstBool [false])
  1648  (EqPtr  (Addr {x} _) (Addr {y} _)) => (ConstBool [x == y])
  1649  (EqPtr  (Addr {x} _) (OffPtr [o] (Addr {y} _))) => (ConstBool [x == y && o == 0])
  1650  (EqPtr  (OffPtr [o1] (Addr {x} _)) (OffPtr [o2] (Addr {y} _))) => (ConstBool [x == y && o1 == o2])
  1651  (NeqPtr (Addr {x} _) (Addr {y} _)) => (ConstBool [x != y])
  1652  (NeqPtr (Addr {x} _) (OffPtr [o] (Addr {y} _))) => (ConstBool [x != y || o != 0])
  1653  (NeqPtr (OffPtr [o1] (Addr {x} _)) (OffPtr [o2] (Addr {y} _))) => (ConstBool [x != y || o1 != o2])
  1654  (EqPtr  (LocalAddr {x} _ _) (LocalAddr {y} _ _)) => (ConstBool [x == y])
  1655  (EqPtr  (LocalAddr {x} _ _) (OffPtr [o] (LocalAddr {y} _ _))) => (ConstBool [x == y && o == 0])
  1656  (EqPtr  (OffPtr [o1] (LocalAddr {x} _ _)) (OffPtr [o2] (LocalAddr {y} _ _))) => (ConstBool [x == y && o1 == o2])
  1657  (NeqPtr (LocalAddr {x} _ _) (LocalAddr {y} _ _)) => (ConstBool [x != y])
  1658  (NeqPtr (LocalAddr {x} _ _) (OffPtr [o] (LocalAddr {y} _ _))) => (ConstBool [x != y || o != 0])
  1659  (NeqPtr (OffPtr [o1] (LocalAddr {x} _ _)) (OffPtr [o2] (LocalAddr {y} _ _))) => (ConstBool [x != y || o1 != o2])
  1660  (EqPtr  (OffPtr [o1] p1) p2) && isSamePtr(p1, p2) => (ConstBool [o1 == 0])
  1661  (NeqPtr (OffPtr [o1] p1) p2) && isSamePtr(p1, p2) => (ConstBool [o1 != 0])
  1662  (EqPtr  (OffPtr [o1] p1) (OffPtr [o2] p2)) && isSamePtr(p1, p2) => (ConstBool [o1 == o2])
  1663  (NeqPtr (OffPtr [o1] p1) (OffPtr [o2] p2)) && isSamePtr(p1, p2) => (ConstBool [o1 != o2])
  1664  (EqPtr  (Const(32|64) [c]) (Const(32|64) [d])) => (ConstBool [c == d])
  1665  (NeqPtr (Const(32|64) [c]) (Const(32|64) [d])) => (ConstBool [c != d])
  1666  (EqPtr  (Convert (Addr {x} _) _) (Addr {y} _)) => (ConstBool [x==y])
  1667  (NeqPtr (Convert (Addr {x} _) _) (Addr {y} _)) => (ConstBool [x!=y])
  1668  
  1669  (EqPtr  (LocalAddr _ _) (Addr _)) => (ConstBool [false])
  1670  (EqPtr  (OffPtr (LocalAddr _ _)) (Addr _)) => (ConstBool [false])
  1671  (EqPtr  (LocalAddr _ _) (OffPtr (Addr _))) => (ConstBool [false])
  1672  (EqPtr  (OffPtr (LocalAddr _ _)) (OffPtr (Addr _))) => (ConstBool [false])
  1673  (NeqPtr (LocalAddr _ _) (Addr _)) => (ConstBool [true])
  1674  (NeqPtr (OffPtr (LocalAddr _ _)) (Addr _)) => (ConstBool [true])
  1675  (NeqPtr (LocalAddr _ _) (OffPtr (Addr _))) => (ConstBool [true])
  1676  (NeqPtr (OffPtr (LocalAddr _ _)) (OffPtr (Addr _))) => (ConstBool [true])
  1677  
  1678  // Simplify address comparisons.
  1679  (EqPtr  (AddPtr p1 o1) p2) && isSamePtr(p1, p2) => (Not (IsNonNil o1))
  1680  (NeqPtr (AddPtr p1 o1) p2) && isSamePtr(p1, p2) => (IsNonNil o1)
  1681  (EqPtr  (Const(32|64) [0]) p) => (Not (IsNonNil p))
  1682  (NeqPtr (Const(32|64) [0]) p) => (IsNonNil p)
  1683  (EqPtr  (ConstNil) p) => (Not (IsNonNil p))
  1684  (NeqPtr (ConstNil) p) => (IsNonNil p)
  1685  
  1686  // Evaluate constant user nil checks.
  1687  (IsNonNil (ConstNil)) => (ConstBool [false])
  1688  (IsNonNil (Const(32|64) [c])) => (ConstBool [c != 0])
  1689  (IsNonNil          (Addr _)   ) => (ConstBool [true])
  1690  (IsNonNil (Convert (Addr _) _)) => (ConstBool [true])
  1691  (IsNonNil (LocalAddr _ _)) => (ConstBool [true])
  1692  
  1693  // Inline small or disjoint runtime.memmove calls with constant length.
  1694  // See the comment in op Move in genericOps.go for discussion of the type.
  1695  //
  1696  // Note that we've lost any knowledge of the type and alignment requirements
  1697  // of the source and destination. We only know the size, and that the type
  1698  // contains no pointers.
  1699  // The type of the move is not necessarily v.Args[0].Type().Elem()!
  1700  // See issue 55122 for details.
  1701  //
  1702  // Because expand calls runs after prove, constants useful to this pattern may not appear.
  1703  // Both versions need to exist; the memory and register variants.
  1704  //
  1705  // Match post-expansion calls, memory version.
  1706  (SelectN [0] call:(StaticCall {sym} s1:(Store _ (Const(64|32) [sz]) s2:(Store  _ src s3:(Store {t} _ dst mem)))))
  1707  	&& sz >= 0
  1708  	&& isSameCall(sym, "runtime.memmove")
  1709  	&& s1.Uses == 1 && s2.Uses == 1 && s3.Uses == 1
  1710  	&& isInlinableMemmove(dst, src, int64(sz), config)
  1711  	&& clobber(s1, s2, s3, call)
  1712  	=> (Move {types.Types[types.TUINT8]} [int64(sz)] dst src mem)
  1713  
  1714  // Match post-expansion calls, register version.
  1715  (SelectN [0] call:(StaticCall {sym} dst src (Const(64|32) [sz]) mem))
  1716  	&& sz >= 0
  1717  	&& call.Uses == 1 // this will exclude all calls with results
  1718  	&& isSameCall(sym, "runtime.memmove")
  1719  	&& isInlinableMemmove(dst, src, int64(sz), config)
  1720  	&& clobber(call)
  1721  	=> (Move {types.Types[types.TUINT8]} [int64(sz)] dst src mem)
  1722  
  1723  // Match pre-expansion calls.
  1724  (SelectN [0] call:(StaticLECall {sym} dst src (Const(64|32) [sz]) mem))
  1725  	&& sz >= 0
  1726  	&& call.Uses == 1 // this will exclude all calls with results
  1727  	&& isSameCall(sym, "runtime.memmove")
  1728  	&& isInlinableMemmove(dst, src, int64(sz), config)
  1729  	&& clobber(call)
  1730  	=> (Move {types.Types[types.TUINT8]} [int64(sz)] dst src mem)
  1731  
  1732  // De-virtualize late-expanded interface calls into late-expanded static calls.
  1733  (InterLECall [argsize] {auxCall} (Addr {fn} (SB)) ___) => devirtLECall(v, fn.(*obj.LSym))
  1734  
  1735  // Move and Zero optimizations.
  1736  // Move source and destination may overlap.
  1737  
  1738  // Convert Moves into Zeros when the source is known to be zeros.
  1739  (Move {t} [n] dst1 src mem:(Zero {t} [n] dst2 _)) && isSamePtr(src, dst2)
  1740  	=> (Zero {t} [n] dst1 mem)
  1741  (Move {t} [n] dst1 src mem:(VarDef (Zero {t} [n] dst0 _))) && isSamePtr(src, dst0)
  1742  	=> (Zero {t} [n] dst1 mem)
  1743  (Move {t} [n] dst (Addr {sym} (SB)) mem) && symIsROZero(sym) => (Zero {t} [n] dst mem)
  1744  
  1745  // Don't Store to variables that are about to be overwritten by Move/Zero.
  1746  (Zero {t1} [n] p1 store:(Store {t2} (OffPtr [o2] p2) _ mem))
  1747  	&& isSamePtr(p1, p2) && store.Uses == 1
  1748  	&& n >= o2 + t2.Size()
  1749  	&& clobber(store)
  1750  	=> (Zero {t1} [n] p1 mem)
  1751  (Move {t1} [n] dst1 src1 store:(Store {t2} op:(OffPtr [o2] dst2) _ mem))
  1752  	&& isSamePtr(dst1, dst2) && store.Uses == 1
  1753  	&& n >= o2 + t2.Size()
  1754  	&& disjoint(src1, n, op, t2.Size())
  1755  	&& clobber(store)
  1756  	=> (Move {t1} [n] dst1 src1 mem)
  1757  
  1758  // Don't Move to variables that are immediately completely overwritten.
  1759  (Zero {t} [n] dst1 move:(Move {t} [n] dst2 _ mem))
  1760  	&& move.Uses == 1
  1761  	&& isSamePtr(dst1, dst2)
  1762  	&& clobber(move)
  1763  	=> (Zero {t} [n] dst1 mem)
  1764  (Move {t} [n] dst1 src1 move:(Move {t} [n] dst2 _ mem))
  1765  	&& move.Uses == 1
  1766  	&& isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
  1767  	&& clobber(move)
  1768  	=> (Move {t} [n] dst1 src1 mem)
  1769  (Zero {t} [n] dst1 vardef:(VarDef {x} move:(Move {t} [n] dst2 _ mem)))
  1770  	&& move.Uses == 1 && vardef.Uses == 1
  1771  	&& isSamePtr(dst1, dst2)
  1772  	&& clobber(move, vardef)
  1773  	=> (Zero {t} [n] dst1 (VarDef {x} mem))
  1774  (Move {t} [n] dst1 src1 vardef:(VarDef {x} move:(Move {t} [n] dst2 _ mem)))
  1775  	&& move.Uses == 1 && vardef.Uses == 1
  1776  	&& isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
  1777  	&& clobber(move, vardef)
  1778  	=> (Move {t} [n] dst1 src1 (VarDef {x} mem))
  1779  (Store {t1} op1:(OffPtr [o1] p1) d1
  1780  	m2:(Store {t2} op2:(OffPtr [0] p2) d2
  1781  		m3:(Move [n] p3 _ mem)))
  1782  	&& m2.Uses == 1 && m3.Uses == 1
  1783  	&& o1 == t2.Size()
  1784  	&& n == t2.Size() + t1.Size()
  1785  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3)
  1786  	&& clobber(m2, m3)
  1787  	=> (Store {t1} op1 d1 (Store {t2} op2 d2 mem))
  1788  (Store {t1} op1:(OffPtr [o1] p1) d1
  1789  	m2:(Store {t2} op2:(OffPtr [o2] p2) d2
  1790  		m3:(Store {t3} op3:(OffPtr [0] p3) d3
  1791  			m4:(Move [n] p4 _ mem))))
  1792  	&& m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1
  1793  	&& o2 == t3.Size()
  1794  	&& o1-o2 == t2.Size()
  1795  	&& n == t3.Size() + t2.Size() + t1.Size()
  1796  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
  1797  	&& clobber(m2, m3, m4)
  1798  	=> (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 mem)))
  1799  (Store {t1} op1:(OffPtr [o1] p1) d1
  1800  	m2:(Store {t2} op2:(OffPtr [o2] p2) d2
  1801  		m3:(Store {t3} op3:(OffPtr [o3] p3) d3
  1802  			m4:(Store {t4} op4:(OffPtr [0] p4) d4
  1803  				m5:(Move [n] p5 _ mem)))))
  1804  	&& m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1 && m5.Uses == 1
  1805  	&& o3 == t4.Size()
  1806  	&& o2-o3 == t3.Size()
  1807  	&& o1-o2 == t2.Size()
  1808  	&& n == t4.Size() + t3.Size() + t2.Size() + t1.Size()
  1809  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
  1810  	&& clobber(m2, m3, m4, m5)
  1811  	=> (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 (Store {t4} op4 d4 mem))))
  1812  
  1813  // Don't Zero variables that are immediately completely overwritten
  1814  // before being accessed.
  1815  (Move {t} [n] dst1 src1 zero:(Zero {t} [n] dst2 mem))
  1816  	&& zero.Uses == 1
  1817  	&& isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
  1818  	&& clobber(zero)
  1819  	=> (Move {t} [n] dst1 src1 mem)
  1820  (Move {t} [n] dst1 src1 vardef:(VarDef {x} zero:(Zero {t} [n] dst2 mem)))
  1821  	&& zero.Uses == 1 && vardef.Uses == 1
  1822  	&& isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
  1823  	&& clobber(zero, vardef)
  1824  	=> (Move {t} [n] dst1 src1 (VarDef {x} mem))
  1825  (Store {t1} op1:(OffPtr [o1] p1) d1
  1826  	m2:(Store {t2} op2:(OffPtr [0] p2) d2
  1827  		m3:(Zero [n] p3 mem)))
  1828  	&& m2.Uses == 1 && m3.Uses == 1
  1829  	&& o1 == t2.Size()
  1830  	&& n == t2.Size() + t1.Size()
  1831  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3)
  1832  	&& clobber(m2, m3)
  1833  	=> (Store {t1} op1 d1 (Store {t2} op2 d2 mem))
  1834  (Store {t1} op1:(OffPtr [o1] p1) d1
  1835  	m2:(Store {t2} op2:(OffPtr [o2] p2) d2
  1836  		m3:(Store {t3} op3:(OffPtr [0] p3) d3
  1837  			m4:(Zero [n] p4 mem))))
  1838  	&& m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1
  1839  	&& o2 == t3.Size()
  1840  	&& o1-o2 == t2.Size()
  1841  	&& n == t3.Size() + t2.Size() + t1.Size()
  1842  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
  1843  	&& clobber(m2, m3, m4)
  1844  	=> (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 mem)))
  1845  (Store {t1} op1:(OffPtr [o1] p1) d1
  1846  	m2:(Store {t2} op2:(OffPtr [o2] p2) d2
  1847  		m3:(Store {t3} op3:(OffPtr [o3] p3) d3
  1848  			m4:(Store {t4} op4:(OffPtr [0] p4) d4
  1849  				m5:(Zero [n] p5 mem)))))
  1850  	&& m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1 && m5.Uses == 1
  1851  	&& o3 == t4.Size()
  1852  	&& o2-o3 == t3.Size()
  1853  	&& o1-o2 == t2.Size()
  1854  	&& n == t4.Size() + t3.Size() + t2.Size() + t1.Size()
  1855  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
  1856  	&& clobber(m2, m3, m4, m5)
  1857  	=> (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 (Store {t4} op4 d4 mem))))
  1858  
  1859  // Don't Move from memory if the values are likely to already be
  1860  // in registers.
  1861  (Move {t1} [n] dst p1
  1862  	mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
  1863  		(Store {t3} op3:(OffPtr <tt3> [0] p3) d2 _)))
  1864  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3)
  1865  	&& t2.Alignment() <= t1.Alignment()
  1866  	&& t3.Alignment() <= t1.Alignment()
  1867  	&& registerizable(b, t2)
  1868  	&& registerizable(b, t3)
  1869  	&& o2 == t3.Size()
  1870  	&& n == t2.Size() + t3.Size()
  1871  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  1872  		(Store {t3} (OffPtr <tt3> [0] dst) d2 mem))
  1873  (Move {t1} [n] dst p1
  1874  	mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
  1875  		(Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
  1876  			(Store {t4} op4:(OffPtr <tt4> [0] p4) d3 _))))
  1877  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
  1878  	&& t2.Alignment() <= t1.Alignment()
  1879  	&& t3.Alignment() <= t1.Alignment()
  1880  	&& t4.Alignment() <= t1.Alignment()
  1881  	&& registerizable(b, t2)
  1882  	&& registerizable(b, t3)
  1883  	&& registerizable(b, t4)
  1884  	&& o3 == t4.Size()
  1885  	&& o2-o3 == t3.Size()
  1886  	&& n == t2.Size() + t3.Size() + t4.Size()
  1887  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  1888  		(Store {t3} (OffPtr <tt3> [o3] dst) d2
  1889  			(Store {t4} (OffPtr <tt4> [0] dst) d3 mem)))
  1890  (Move {t1} [n] dst p1
  1891  	mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
  1892  		(Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
  1893  			(Store {t4} op4:(OffPtr <tt4> [o4] p4) d3
  1894  				(Store {t5} op5:(OffPtr <tt5> [0] p5) d4 _)))))
  1895  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
  1896  	&& t2.Alignment() <= t1.Alignment()
  1897  	&& t3.Alignment() <= t1.Alignment()
  1898  	&& t4.Alignment() <= t1.Alignment()
  1899  	&& t5.Alignment() <= t1.Alignment()
  1900  	&& registerizable(b, t2)
  1901  	&& registerizable(b, t3)
  1902  	&& registerizable(b, t4)
  1903  	&& registerizable(b, t5)
  1904  	&& o4 == t5.Size()
  1905  	&& o3-o4 == t4.Size()
  1906  	&& o2-o3 == t3.Size()
  1907  	&& n == t2.Size() + t3.Size() + t4.Size() + t5.Size()
  1908  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  1909  		(Store {t3} (OffPtr <tt3> [o3] dst) d2
  1910  			(Store {t4} (OffPtr <tt4> [o4] dst) d3
  1911  				(Store {t5} (OffPtr <tt5> [0] dst) d4 mem))))
  1912  
  1913  // Same thing but with VarDef in the middle.
  1914  (Move {t1} [n] dst p1
  1915  	mem:(VarDef
  1916  		(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
  1917  			(Store {t3} op3:(OffPtr <tt3> [0] p3) d2 _))))
  1918  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3)
  1919  	&& t2.Alignment() <= t1.Alignment()
  1920  	&& t3.Alignment() <= t1.Alignment()
  1921  	&& registerizable(b, t2)
  1922  	&& registerizable(b, t3)
  1923  	&& o2 == t3.Size()
  1924  	&& n == t2.Size() + t3.Size()
  1925  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  1926  		(Store {t3} (OffPtr <tt3> [0] dst) d2 mem))
  1927  (Move {t1} [n] dst p1
  1928  	mem:(VarDef
  1929  		(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
  1930  			(Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
  1931  				(Store {t4} op4:(OffPtr <tt4> [0] p4) d3 _)))))
  1932  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
  1933  	&& t2.Alignment() <= t1.Alignment()
  1934  	&& t3.Alignment() <= t1.Alignment()
  1935  	&& t4.Alignment() <= t1.Alignment()
  1936  	&& registerizable(b, t2)
  1937  	&& registerizable(b, t3)
  1938  	&& registerizable(b, t4)
  1939  	&& o3 == t4.Size()
  1940  	&& o2-o3 == t3.Size()
  1941  	&& n == t2.Size() + t3.Size() + t4.Size()
  1942  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  1943  		(Store {t3} (OffPtr <tt3> [o3] dst) d2
  1944  			(Store {t4} (OffPtr <tt4> [0] dst) d3 mem)))
  1945  (Move {t1} [n] dst p1
  1946  	mem:(VarDef
  1947  		(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
  1948  			(Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
  1949  				(Store {t4} op4:(OffPtr <tt4> [o4] p4) d3
  1950  					(Store {t5} op5:(OffPtr <tt5> [0] p5) d4 _))))))
  1951  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
  1952  	&& t2.Alignment() <= t1.Alignment()
  1953  	&& t3.Alignment() <= t1.Alignment()
  1954  	&& t4.Alignment() <= t1.Alignment()
  1955  	&& t5.Alignment() <= t1.Alignment()
  1956  	&& registerizable(b, t2)
  1957  	&& registerizable(b, t3)
  1958  	&& registerizable(b, t4)
  1959  	&& registerizable(b, t5)
  1960  	&& o4 == t5.Size()
  1961  	&& o3-o4 == t4.Size()
  1962  	&& o2-o3 == t3.Size()
  1963  	&& n == t2.Size() + t3.Size() + t4.Size() + t5.Size()
  1964  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  1965  		(Store {t3} (OffPtr <tt3> [o3] dst) d2
  1966  			(Store {t4} (OffPtr <tt4> [o4] dst) d3
  1967  				(Store {t5} (OffPtr <tt5> [0] dst) d4 mem))))
  1968  
  1969  // Prefer to Zero and Store than to Move.
  1970  (Move {t1} [n] dst p1
  1971  	mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
  1972  		(Zero {t3} [n] p3 _)))
  1973  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3)
  1974  	&& t2.Alignment() <= t1.Alignment()
  1975  	&& t3.Alignment() <= t1.Alignment()
  1976  	&& registerizable(b, t2)
  1977  	&& n >= o2 + t2.Size()
  1978  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  1979  		(Zero {t1} [n] dst mem))
  1980  (Move {t1} [n] dst p1
  1981  	mem:(Store {t2} (OffPtr <tt2> [o2] p2) d1
  1982  		(Store {t3} (OffPtr <tt3> [o3] p3) d2
  1983  			(Zero {t4} [n] p4 _))))
  1984  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
  1985  	&& t2.Alignment() <= t1.Alignment()
  1986  	&& t3.Alignment() <= t1.Alignment()
  1987  	&& t4.Alignment() <= t1.Alignment()
  1988  	&& registerizable(b, t2)
  1989  	&& registerizable(b, t3)
  1990  	&& n >= o2 + t2.Size()
  1991  	&& n >= o3 + t3.Size()
  1992  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  1993  		(Store {t3} (OffPtr <tt3> [o3] dst) d2
  1994  			(Zero {t1} [n] dst mem)))
  1995  (Move {t1} [n] dst p1
  1996  	mem:(Store {t2} (OffPtr <tt2> [o2] p2) d1
  1997  		(Store {t3} (OffPtr <tt3> [o3] p3) d2
  1998  			(Store {t4} (OffPtr <tt4> [o4] p4) d3
  1999  				(Zero {t5} [n] p5 _)))))
  2000  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
  2001  	&& t2.Alignment() <= t1.Alignment()
  2002  	&& t3.Alignment() <= t1.Alignment()
  2003  	&& t4.Alignment() <= t1.Alignment()
  2004  	&& t5.Alignment() <= t1.Alignment()
  2005  	&& registerizable(b, t2)
  2006  	&& registerizable(b, t3)
  2007  	&& registerizable(b, t4)
  2008  	&& n >= o2 + t2.Size()
  2009  	&& n >= o3 + t3.Size()
  2010  	&& n >= o4 + t4.Size()
  2011  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  2012  		(Store {t3} (OffPtr <tt3> [o3] dst) d2
  2013  			(Store {t4} (OffPtr <tt4> [o4] dst) d3
  2014  				(Zero {t1} [n] dst mem))))
  2015  (Move {t1} [n] dst p1
  2016  	mem:(Store {t2} (OffPtr <tt2> [o2] p2) d1
  2017  		(Store {t3} (OffPtr <tt3> [o3] p3) d2
  2018  			(Store {t4} (OffPtr <tt4> [o4] p4) d3
  2019  				(Store {t5} (OffPtr <tt5> [o5] p5) d4
  2020  					(Zero {t6} [n] p6 _))))))
  2021  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5) && isSamePtr(p5, p6)
  2022  	&& t2.Alignment() <= t1.Alignment()
  2023  	&& t3.Alignment() <= t1.Alignment()
  2024  	&& t4.Alignment() <= t1.Alignment()
  2025  	&& t5.Alignment() <= t1.Alignment()
  2026  	&& t6.Alignment() <= t1.Alignment()
  2027  	&& registerizable(b, t2)
  2028  	&& registerizable(b, t3)
  2029  	&& registerizable(b, t4)
  2030  	&& registerizable(b, t5)
  2031  	&& n >= o2 + t2.Size()
  2032  	&& n >= o3 + t3.Size()
  2033  	&& n >= o4 + t4.Size()
  2034  	&& n >= o5 + t5.Size()
  2035  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  2036  		(Store {t3} (OffPtr <tt3> [o3] dst) d2
  2037  			(Store {t4} (OffPtr <tt4> [o4] dst) d3
  2038  				(Store {t5} (OffPtr <tt5> [o5] dst) d4
  2039  					(Zero {t1} [n] dst mem)))))
  2040  (Move {t1} [n] dst p1
  2041  	mem:(VarDef
  2042  		(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
  2043  			(Zero {t3} [n] p3 _))))
  2044  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3)
  2045  	&& t2.Alignment() <= t1.Alignment()
  2046  	&& t3.Alignment() <= t1.Alignment()
  2047  	&& registerizable(b, t2)
  2048  	&& n >= o2 + t2.Size()
  2049  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  2050  		(Zero {t1} [n] dst mem))
  2051  (Move {t1} [n] dst p1
  2052  	mem:(VarDef
  2053  		(Store {t2} (OffPtr <tt2> [o2] p2) d1
  2054  			(Store {t3} (OffPtr <tt3> [o3] p3) d2
  2055  				(Zero {t4} [n] p4 _)))))
  2056  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
  2057  	&& t2.Alignment() <= t1.Alignment()
  2058  	&& t3.Alignment() <= t1.Alignment()
  2059  	&& t4.Alignment() <= t1.Alignment()
  2060  	&& registerizable(b, t2)
  2061  	&& registerizable(b, t3)
  2062  	&& n >= o2 + t2.Size()
  2063  	&& n >= o3 + t3.Size()
  2064  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  2065  		(Store {t3} (OffPtr <tt3> [o3] dst) d2
  2066  			(Zero {t1} [n] dst mem)))
  2067  (Move {t1} [n] dst p1
  2068  	mem:(VarDef
  2069  		(Store {t2} (OffPtr <tt2> [o2] p2) d1
  2070  			(Store {t3} (OffPtr <tt3> [o3] p3) d2
  2071  				(Store {t4} (OffPtr <tt4> [o4] p4) d3
  2072  					(Zero {t5} [n] p5 _))))))
  2073  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
  2074  	&& t2.Alignment() <= t1.Alignment()
  2075  	&& t3.Alignment() <= t1.Alignment()
  2076  	&& t4.Alignment() <= t1.Alignment()
  2077  	&& t5.Alignment() <= t1.Alignment()
  2078  	&& registerizable(b, t2)
  2079  	&& registerizable(b, t3)
  2080  	&& registerizable(b, t4)
  2081  	&& n >= o2 + t2.Size()
  2082  	&& n >= o3 + t3.Size()
  2083  	&& n >= o4 + t4.Size()
  2084  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  2085  		(Store {t3} (OffPtr <tt3> [o3] dst) d2
  2086  			(Store {t4} (OffPtr <tt4> [o4] dst) d3
  2087  				(Zero {t1} [n] dst mem))))
  2088  (Move {t1} [n] dst p1
  2089  	mem:(VarDef
  2090  		(Store {t2} (OffPtr <tt2> [o2] p2) d1
  2091  			(Store {t3} (OffPtr <tt3> [o3] p3) d2
  2092  				(Store {t4} (OffPtr <tt4> [o4] p4) d3
  2093  					(Store {t5} (OffPtr <tt5> [o5] p5) d4
  2094  						(Zero {t6} [n] p6 _)))))))
  2095  	&& isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5) && isSamePtr(p5, p6)
  2096  	&& t2.Alignment() <= t1.Alignment()
  2097  	&& t3.Alignment() <= t1.Alignment()
  2098  	&& t4.Alignment() <= t1.Alignment()
  2099  	&& t5.Alignment() <= t1.Alignment()
  2100  	&& t6.Alignment() <= t1.Alignment()
  2101  	&& registerizable(b, t2)
  2102  	&& registerizable(b, t3)
  2103  	&& registerizable(b, t4)
  2104  	&& registerizable(b, t5)
  2105  	&& n >= o2 + t2.Size()
  2106  	&& n >= o3 + t3.Size()
  2107  	&& n >= o4 + t4.Size()
  2108  	&& n >= o5 + t5.Size()
  2109  	=> (Store {t2} (OffPtr <tt2> [o2] dst) d1
  2110  		(Store {t3} (OffPtr <tt3> [o3] dst) d2
  2111  			(Store {t4} (OffPtr <tt4> [o4] dst) d3
  2112  				(Store {t5} (OffPtr <tt5> [o5] dst) d4
  2113  					(Zero {t1} [n] dst mem)))))
  2114  
  2115  (SelectN [0] call:(StaticLECall {sym} a x)) && needRaceCleanup(sym, call) && clobber(call) => x
  2116  (SelectN [0] call:(StaticLECall {sym} x)) && needRaceCleanup(sym, call) && clobber(call) => x
  2117  
  2118  // When rewriting append to growslice, we use as the new length the result of
  2119  // growslice so that we don't have to spill/restore the new length around the growslice call.
  2120  // The exception here is that if the new length is a constant, avoiding spilling it
  2121  // is pointless and its constantness is sometimes useful for subsequent optimizations.
  2122  // See issue 56440.
  2123  // Note there are 2 rules here, one for the pre-decomposed []T result and one for
  2124  // the post-decomposed (*T,int,int) result. (The latter is generated after call expansion.)
  2125  // TODO(thepudds): we probably need the new growsliceBuf and growsliceBufNoAlias here as well?
  2126  (SliceLen (SelectN [0] (StaticLECall {sym} _ newLen:(Const(64|32)) _ _ _ _)))
  2127  	&& (isSameCall(sym, "runtime.growslice") || isSameCall(sym, "runtime.growsliceNoAlias"))
  2128  	=> newLen
  2129  (SelectN [1] (StaticCall {sym} _ newLen:(Const(64|32)) _ _ _ _)) && v.Type.IsInteger()
  2130  	&& (isSameCall(sym, "runtime.growslice") || isSameCall(sym, "runtime.growsliceNoAlias"))
  2131  	=> newLen
  2132  
  2133  // Collapse moving A -> B -> C into just A -> C.
  2134  // Later passes (deadstore, elim unread auto) will remove the A -> B move, if possible.
  2135  // This happens most commonly when B is an autotmp inserted earlier
  2136  // during compilation to ensure correctness.
  2137  // Take care that overlapping moves are preserved.
  2138  // Restrict this optimization to the stack, to avoid duplicating loads from the heap;
  2139  // see CL 145208 for discussion.
  2140  (Move {t1} [s] dst tmp1 midmem:(Move {t2} [s] tmp2 src _))
  2141  	&& t1.Compare(t2) == types.CMPeq
  2142  	&& isSamePtr(tmp1, tmp2)
  2143  	&& isStackPtr(src) && !isVolatile(src)
  2144  	&& disjoint(src, s, tmp2, s)
  2145  	&& (disjoint(src, s, dst, s) || isInlinableMemmove(dst, src, s, config))
  2146  	=> (Move {t1} [s] dst src midmem)
  2147  
  2148  // Same, but for large types that require VarDefs.
  2149  (Move {t1} [s] dst tmp1 midmem:(VarDef (Move {t2} [s] tmp2 src _)))
  2150  	&& t1.Compare(t2) == types.CMPeq
  2151  	&& isSamePtr(tmp1, tmp2)
  2152  	&& isStackPtr(src) && !isVolatile(src)
  2153  	&& disjoint(src, s, tmp2, s)
  2154  	&& (disjoint(src, s, dst, s) || isInlinableMemmove(dst, src, s, config))
  2155  	=> (Move {t1} [s] dst src midmem)
  2156  
  2157  // Don't zero the same bits twice.
  2158  (Zero {t} [s] dst1 zero:(Zero {t} [s] dst2 _)) && isSamePtr(dst1, dst2) => zero
  2159  (Zero {t} [s] dst1 vardef:(VarDef (Zero {t} [s] dst2 _))) && isSamePtr(dst1, dst2) => vardef
  2160  
  2161  // Elide self-moves. This only happens rarely (e.g test/fixedbugs/bug277.go).
  2162  // However, this rule is needed to prevent the previous rule from looping forever in such cases.
  2163  (Move dst src mem) && isSamePtr(dst, src) => mem
  2164  
  2165  // Constant rotate detection.
  2166  ((Add64|Or64|Xor64) (Lsh64x64 x z:(Const64 <t> [c])) (Rsh64Ux64 x (Const64 [d]))) && c < 64 && d == 64-c && canRotate(config, 64) => (RotateLeft64 x z)
  2167  ((Add32|Or32|Xor32) (Lsh32x64 x z:(Const64 <t> [c])) (Rsh32Ux64 x (Const64 [d]))) && c < 32 && d == 32-c && canRotate(config, 32) => (RotateLeft32 x z)
  2168  ((Add16|Or16|Xor16) (Lsh16x64 x z:(Const64 <t> [c])) (Rsh16Ux64 x (Const64 [d]))) && c < 16 && d == 16-c && canRotate(config, 16) => (RotateLeft16 x z)
  2169  ((Add8|Or8|Xor8) (Lsh8x64 x z:(Const64 <t> [c])) (Rsh8Ux64 x (Const64 [d]))) && c < 8 && d == 8-c && canRotate(config, 8) => (RotateLeft8 x z)
  2170  
  2171  // Non-constant rotate detection.
  2172  // We use shiftIsBounded to make sure that neither of the shifts are >64.
  2173  // Note: these rules are subtle when the shift amounts are 0/64, as Go shifts
  2174  // are different from most native shifts. But it works out.
  2175  ((Add64|Or64|Xor64) left:(Lsh64x64 x y) right:(Rsh64Ux64 x (Sub64 (Const64 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
  2176  ((Add64|Or64|Xor64) left:(Lsh64x32 x y) right:(Rsh64Ux32 x (Sub32 (Const32 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
  2177  ((Add64|Or64|Xor64) left:(Lsh64x16 x y) right:(Rsh64Ux16 x (Sub16 (Const16 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
  2178  ((Add64|Or64|Xor64) left:(Lsh64x8  x y) right:(Rsh64Ux8  x (Sub8  (Const8  [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
  2179  
  2180  ((Add64|Or64|Xor64) right:(Rsh64Ux64 x y) left:(Lsh64x64 x z:(Sub64 (Const64 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
  2181  ((Add64|Or64|Xor64) right:(Rsh64Ux32 x y) left:(Lsh64x32 x z:(Sub32 (Const32 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
  2182  ((Add64|Or64|Xor64) right:(Rsh64Ux16 x y) left:(Lsh64x16 x z:(Sub16 (Const16 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
  2183  ((Add64|Or64|Xor64) right:(Rsh64Ux8  x y) left:(Lsh64x8  x z:(Sub8  (Const8  [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
  2184  
  2185  ((Add32|Or32|Xor32) left:(Lsh32x64 x y) right:(Rsh32Ux64 x (Sub64 (Const64 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
  2186  ((Add32|Or32|Xor32) left:(Lsh32x32 x y) right:(Rsh32Ux32 x (Sub32 (Const32 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
  2187  ((Add32|Or32|Xor32) left:(Lsh32x16 x y) right:(Rsh32Ux16 x (Sub16 (Const16 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
  2188  ((Add32|Or32|Xor32) left:(Lsh32x8  x y) right:(Rsh32Ux8  x (Sub8  (Const8  [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
  2189  
  2190  ((Add32|Or32|Xor32) right:(Rsh32Ux64 x y) left:(Lsh32x64 x z:(Sub64 (Const64 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
  2191  ((Add32|Or32|Xor32) right:(Rsh32Ux32 x y) left:(Lsh32x32 x z:(Sub32 (Const32 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
  2192  ((Add32|Or32|Xor32) right:(Rsh32Ux16 x y) left:(Lsh32x16 x z:(Sub16 (Const16 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
  2193  ((Add32|Or32|Xor32) right:(Rsh32Ux8  x y) left:(Lsh32x8  x z:(Sub8  (Const8  [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
  2194  
  2195  ((Add16|Or16|Xor16) left:(Lsh16x64 x y) right:(Rsh16Ux64 x (Sub64 (Const64 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
  2196  ((Add16|Or16|Xor16) left:(Lsh16x32 x y) right:(Rsh16Ux32 x (Sub32 (Const32 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
  2197  ((Add16|Or16|Xor16) left:(Lsh16x16 x y) right:(Rsh16Ux16 x (Sub16 (Const16 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
  2198  ((Add16|Or16|Xor16) left:(Lsh16x8  x y) right:(Rsh16Ux8  x (Sub8  (Const8  [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
  2199  
  2200  ((Add16|Or16|Xor16) right:(Rsh16Ux64 x y) left:(Lsh16x64 x z:(Sub64 (Const64 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
  2201  ((Add16|Or16|Xor16) right:(Rsh16Ux32 x y) left:(Lsh16x32 x z:(Sub32 (Const32 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
  2202  ((Add16|Or16|Xor16) right:(Rsh16Ux16 x y) left:(Lsh16x16 x z:(Sub16 (Const16 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
  2203  ((Add16|Or16|Xor16) right:(Rsh16Ux8  x y) left:(Lsh16x8  x z:(Sub8  (Const8  [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
  2204  
  2205  ((Add8|Or8|Xor8) left:(Lsh8x64 x y) right:(Rsh8Ux64 x (Sub64 (Const64 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
  2206  ((Add8|Or8|Xor8) left:(Lsh8x32 x y) right:(Rsh8Ux32 x (Sub32 (Const32 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
  2207  ((Add8|Or8|Xor8) left:(Lsh8x16 x y) right:(Rsh8Ux16 x (Sub16 (Const16 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
  2208  ((Add8|Or8|Xor8) left:(Lsh8x8  x y) right:(Rsh8Ux8  x (Sub8  (Const8  [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
  2209  
  2210  ((Add8|Or8|Xor8) right:(Rsh8Ux64 x y) left:(Lsh8x64 x z:(Sub64 (Const64 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
  2211  ((Add8|Or8|Xor8) right:(Rsh8Ux32 x y) left:(Lsh8x32 x z:(Sub32 (Const32 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
  2212  ((Add8|Or8|Xor8) right:(Rsh8Ux16 x y) left:(Lsh8x16 x z:(Sub16 (Const16 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
  2213  ((Add8|Or8|Xor8) right:(Rsh8Ux8  x y) left:(Lsh8x8  x z:(Sub8  (Const8  [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
  2214  
  2215  // Rotating by y&c, with c a mask that doesn't change the bottom bits, is the same as rotating by y.
  2216  (RotateLeft64 x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&63 == 63 => (RotateLeft64 x y)
  2217  (RotateLeft32 x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&31 == 31 => (RotateLeft32 x y)
  2218  (RotateLeft16 x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&15 == 15 => (RotateLeft16 x y)
  2219  (RotateLeft8  x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&7  == 7  => (RotateLeft8  x y)
  2220  
  2221  // Rotating by -(y&c), with c a mask that doesn't change the bottom bits, is the same as rotating by -y.
  2222  (RotateLeft64 x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&63 == 63 => (RotateLeft64 x (Neg(64|32|16|8) <y.Type> y))
  2223  (RotateLeft32 x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&31 == 31 => (RotateLeft32 x (Neg(64|32|16|8) <y.Type> y))
  2224  (RotateLeft16 x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&15 == 15 => (RotateLeft16 x (Neg(64|32|16|8) <y.Type> y))
  2225  (RotateLeft8  x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&7  == 7  => (RotateLeft8  x (Neg(64|32|16|8) <y.Type> y))
  2226  
  2227  // Rotating by y+c, with c a multiple of the value width, is the same as rotating by y.
  2228  (RotateLeft64 x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&63 == 0 => (RotateLeft64 x y)
  2229  (RotateLeft32 x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&31 == 0 => (RotateLeft32 x y)
  2230  (RotateLeft16 x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&15 == 0 => (RotateLeft16 x y)
  2231  (RotateLeft8  x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&7  == 0 => (RotateLeft8  x y)
  2232  
  2233  // Rotating by c-y, with c a multiple of the value width, is the same as rotating by -y.
  2234  (RotateLeft64 x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&63 == 0 => (RotateLeft64 x (Neg(64|32|16|8) <y.Type> y))
  2235  (RotateLeft32 x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&31 == 0 => (RotateLeft32 x (Neg(64|32|16|8) <y.Type> y))
  2236  (RotateLeft16 x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&15 == 0 => (RotateLeft16 x (Neg(64|32|16|8) <y.Type> y))
  2237  (RotateLeft8  x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&7  == 0 => (RotateLeft8  x (Neg(64|32|16|8) <y.Type> y))
  2238  
  2239  // Ensure we don't do Const64 rotates in a 32-bit system.
  2240  (RotateLeft64 x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft64 x (Const32 <t> [int32(c)]))
  2241  (RotateLeft32 x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft32 x (Const32 <t> [int32(c)]))
  2242  (RotateLeft16 x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft16 x (Const32 <t> [int32(c)]))
  2243  (RotateLeft8  x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft8  x (Const32 <t> [int32(c)]))
  2244  
  2245  // Rotating by c, then by d, is the same as rotating by c+d.
  2246  // We're trading a rotate for an add, which seems generally a good choice. It is especially good when c and d are constants.
  2247  // This rule is a bit tricky as c and d might be different widths. We handle only cases where they are the same width.
  2248  (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 8 && d.Type.Size() == 8 => (RotateLeft(64|32|16|8) x (Add64 <c.Type> c d))
  2249  (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 4 && d.Type.Size() == 4 => (RotateLeft(64|32|16|8) x (Add32 <c.Type> c d))
  2250  (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 2 && d.Type.Size() == 2 => (RotateLeft(64|32|16|8) x (Add16 <c.Type> c d))
  2251  (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 1 && d.Type.Size() == 1 => (RotateLeft(64|32|16|8) x (Add8  <c.Type> c d))
  2252  
  2253  // Loading fixed addresses and constants.
  2254  (Load                                     (Addr {s} sb)         _)  && isFixedLoad(v, s,   0) => rewriteFixedLoad(v, s, sb,   0)
  2255  (Load                            (Convert (Addr {s} sb) _)      _)  && isFixedLoad(v, s,   0) => rewriteFixedLoad(v, s, sb,   0)
  2256  (Load               (ITab (IMake          (Addr {s} sb)    _))  _)  && isFixedLoad(v, s,   0) => rewriteFixedLoad(v, s, sb,   0)
  2257  (Load               (ITab (IMake (Convert (Addr {s} sb) _) _))  _)  && isFixedLoad(v, s,   0) => rewriteFixedLoad(v, s, sb,   0)
  2258  (Load (OffPtr [off]                       (Addr {s} sb)       ) _)  && isFixedLoad(v, s, off) => rewriteFixedLoad(v, s, sb, off)
  2259  (Load (OffPtr [off]              (Convert (Addr {s} sb) _)    ) _)  && isFixedLoad(v, s, off) => rewriteFixedLoad(v, s, sb, off)
  2260  (Load (OffPtr [off] (ITab (IMake          (Addr {s} sb)    _))) _)  && isFixedLoad(v, s, off) => rewriteFixedLoad(v, s, sb, off)
  2261  (Load (OffPtr [off] (ITab (IMake (Convert (Addr {s} sb) _) _))) _)  && isFixedLoad(v, s, off) => rewriteFixedLoad(v, s, sb, off)
  2262  
  2263  // Calling cmpstring a second time with the same arguments in the
  2264  // same memory state can reuse the results of the first call.
  2265  // See issue 61725.
  2266  // Note that this could pretty easily generalize to any pure function.
  2267  (SelectN [0] (StaticLECall {f} x y (SelectN [1] c:(StaticLECall {g} x y mem))))
  2268    && isSameCall(f, "runtime.cmpstring")
  2269    && isSameCall(g, "runtime.cmpstring")
  2270  => @c.Block (SelectN [0] <typ.Int> c)
  2271  
  2272  // If we don't use the result of cmpstring, might as well not call it.
  2273  // Note that this could pretty easily generalize to any pure function.
  2274  (SelectN [1] c:(StaticLECall {f} _ _ mem)) && c.Uses == 1 && isSameCall(f, "runtime.cmpstring") && clobber(c) => mem
  2275  
  2276  // We can easily compute the result of efaceeq if
  2277  // we know the underlying type is pointer-ish.
  2278  (StaticLECall {f} typ_ x y mem)
  2279  	&& isSameCall(f, "runtime.efaceeq")
  2280  	&& isDirectAndComparableType(typ_)
  2281  	&& clobber(v)
  2282  	=> (MakeResult (EqPtr x y) mem)
  2283  
  2284  // We can easily compute the result of ifaceeq if
  2285  // we know the underlying type is pointer-ish.
  2286  (StaticLECall {f} itab x y mem)
  2287  	&& isSameCall(f, "runtime.ifaceeq")
  2288  	&& isDirectAndComparableIface(itab)
  2289  	&& clobber(v)
  2290  	=> (MakeResult (EqPtr x y) mem)
  2291  
  2292  // If we use the result of slicebytetostring in a map lookup operation,
  2293  // then we don't need to actually do the []byte->string conversion.
  2294  // We can just use the ptr/len of the byte slice directly as a (temporary) string.
  2295  //
  2296  // Note that this does not handle some obscure cases like
  2297  // m[[2]string{string(b1), string(b2)}]. There is code in ../walk/order.go
  2298  // which handles some of those cases.
  2299  (StaticLECall {f} [argsize] typ_ map_ key:(SelectN [0] sbts:(StaticLECall {g} _ ptr len mem)) m:(SelectN [1] sbts))
  2300    &&    (isSameCall(f, "runtime.mapaccess1_faststr")
  2301        || isSameCall(f, "runtime.mapaccess2_faststr")
  2302        || isSameCall(f, "runtime.mapdelete_faststr"))
  2303    && isSameCall(g, "runtime.slicebytetostring")
  2304    && key.Uses == 1
  2305    && sbts.Uses == 2
  2306    && resetCopy(m, mem)
  2307    && clobber(sbts)
  2308    && clobber(key)
  2309  => (StaticLECall {f} [argsize] typ_ map_ (StringMake <typ.String> ptr len) mem)
  2310  
  2311  // Similarly to map lookups, also handle unique.Make for strings, which unique.Make will clone.
  2312  (StaticLECall {f} [argsize] dict_ key:(SelectN [0] sbts:(StaticLECall {g} _ ptr len mem)) m:(SelectN [1] sbts))
  2313    && isSameCall(f, "unique.Make[go.shape.string]")
  2314    && isSameCall(g, "runtime.slicebytetostring")
  2315    && key.Uses == 1
  2316    && sbts.Uses == 2
  2317    && resetCopy(m, mem)
  2318    && clobber(sbts)
  2319    && clobber(key)
  2320  => (StaticLECall {f} [argsize] dict_ (StringMake <typ.String> ptr len) mem)
  2321  
  2322  // Transform some CondSelect into math operations.
  2323  // if b { x += c } => x += b * c
  2324  (CondSelect op:(Add8 <t> x c:(Const8)) x bool) &&
  2325  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2326  	(Add8 x (Mul8 <t> c (CvtBoolToUint8 <t> bool)))
  2327  (CondSelect op:(Add(64|32|16) <t> x c:(Const(64|32|16))) x bool) &&
  2328  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2329  	(Add(64|32|16) x (Mul(64|32|16) <t> c (ZeroExt8to(64|32|16) <t> (CvtBoolToUint8 <types.Types[types.TUINT8]> bool))))
  2330  // if !b { x += c } => x += !b * c
  2331  (CondSelect x op:(Add8 <t> x c:(Const8)) bool) &&
  2332  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2333  	(Add8 x (Mul8 <t> c (CvtBoolToUint8 <t> (Not <bool.Type> bool))))
  2334  (CondSelect x op:(Add(64|32|16) <t> x c:(Const(64|32|16))) bool) &&
  2335  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2336  	(Add(64|32|16) x (Mul(64|32|16) <t> c (ZeroExt8to(64|32|16) <t> (CvtBoolToUint8 <types.Types[types.TUINT8]> (Not <bool.Type> bool)))))
  2337  
  2338  // if b { x += c } => x -= b * -c // looks redundant but useful if the arch can inline materialize -c but not c
  2339  (CondSelect op:(Add8 <t> x c:(Const8 [consT])) x bool) &&
  2340  	!rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) &&
  2341  	rewriteCondSelectIntoMath(config, addToSub(op.Op), -c.AuxInt) =>
  2342  	(Sub8 x (Mul8 <t> (Const8 <t> [-consT]) (CvtBoolToUint8 <t> bool)))
  2343  (CondSelect op:(Add(64|32|16) <t> x c:(Const(64|32|16) [consT])) x bool) &&
  2344  	!rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) &&
  2345  	rewriteCondSelectIntoMath(config, addToSub(op.Op), -c.AuxInt) =>
  2346  	(Sub(64|32|16) x (Mul(64|32|16) <t> (Const(64|32|16) <t> [-consT]) (ZeroExt8to(64|32|16) <t> (CvtBoolToUint8 <types.Types[types.TUINT8]> bool))))
  2347  // if !b { x += c } => x -= !b * -c // looks redundant but useful if the arch can inline materialize -c but not c
  2348  (CondSelect x op:(Add8 <t> x c:(Const8 [consT])) bool) &&
  2349  	!rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) &&
  2350  	rewriteCondSelectIntoMath(config, addToSub(op.Op), -c.AuxInt) =>
  2351  	(Sub8 x (Mul8 <t> (Const8 <t> [-consT]) (CvtBoolToUint8 <t> (Not <bool.Type> bool))))
  2352  (CondSelect x op:(Add(64|32|16) <t> x c:(Const(64|32|16) [consT])) bool) &&
  2353  	!rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) &&
  2354  	rewriteCondSelectIntoMath(config, addToSub(op.Op), -c.AuxInt) =>
  2355  	(Sub(64|32|16) x (Mul(64|32|16) <t> (Const(64|32|16) <t> [-consT]) (ZeroExt8to(64|32|16) <t> (CvtBoolToUint8 <types.Types[types.TUINT8]> (Not <bool.Type> bool)))))
  2356  
  2357  // if b { x <<= 1 } => x <<= b
  2358  (CondSelect (Lsh(64|32|16|8)x64 x (Const64 [1])) x bool) => (Lsh(64|32|16|8)x8 [true] x (CvtBoolToUint8 <types.Types[types.TUINT8]> bool))
  2359  // if !b { x <<= 1 } => x <<= !b
  2360  (CondSelect x (Lsh(64|32|16|8)x64 x (Const64 [1])) bool) => (Lsh(64|32|16|8)x8 [true] x (CvtBoolToUint8 <types.Types[types.TUINT8]> (Not <bool.Type> bool)))
  2361  
  2362  // if b { x >>= 1 } => x >>= b
  2363  (CondSelect (Rsh(64|32|16|8)x64 x (Const64 [1])) x bool) => (Rsh(64|32|16|8)x8 [true] x (CvtBoolToUint8 <types.Types[types.TUINT8]> bool))
  2364  (CondSelect (Rsh(64|32|16|8)Ux64 x (Const64 [1])) x bool) => (Rsh(64|32|16|8)Ux8 [true] x (CvtBoolToUint8 <types.Types[types.TUINT8]> bool))
  2365  // if !b { x >>= 1 } => x >>= !b
  2366  (CondSelect x (Rsh(64|32|16|8)x64 x (Const64 [1])) bool) => (Rsh(64|32|16|8)x8 [true] x (CvtBoolToUint8 <types.Types[types.TUINT8]> (Not <bool.Type> bool)))
  2367  (CondSelect x (Rsh(64|32|16|8)Ux64 x (Const64 [1])) bool) => (Rsh(64|32|16|8)Ux8 [true] x (CvtBoolToUint8 <types.Types[types.TUINT8]> (Not <bool.Type> bool)))
  2368  
  2369  // if b { x |= c } => x |= b * c
  2370  (CondSelect op:(Or8 <t> x c:(Const8)) x bool) &&
  2371  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2372  	(Or8 x (Mul8 <t> c (CvtBoolToUint8 <t> bool)))
  2373  (CondSelect op:(Or(64|32|16) <t> x c:(Const(64|32|16))) x bool) &&
  2374  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2375  	(Or(64|32|16) x (Mul(64|32|16) <t> c (ZeroExt8to(64|32|16) <t> (CvtBoolToUint8 <types.Types[types.TUINT8]> bool))))
  2376  // if !b { x |= c } => x |= !b * c
  2377  (CondSelect x op:(Or8 <t> x c:(Const8)) bool) &&
  2378  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2379  	(Or8 x (Mul8 <t> c (CvtBoolToUint8 <t> (Not <bool.Type> bool))))
  2380  (CondSelect x op:(Or(64|32|16) <t> x c:(Const(64|32|16))) bool) &&
  2381  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2382  	(Or(64|32|16) x (Mul(64|32|16) <t> c (ZeroExt8to(64|32|16) <t> (CvtBoolToUint8 <types.Types[types.TUINT8]> (Not <bool.Type> bool)))))
  2383  
  2384  // if b { x ^= c } => x ^= b * c
  2385  (CondSelect op:(Xor8 <t> x c:(Const8)) x bool) &&
  2386  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2387  	(Xor8 x (Mul8 <t> c (CvtBoolToUint8 <t> bool)))
  2388  (CondSelect op:(Xor(64|32|16) <t> x c:(Const(64|32|16))) x bool) &&
  2389  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2390  	(Xor(64|32|16) x (Mul(64|32|16) <t> c (ZeroExt8to(64|32|16) <t> (CvtBoolToUint8 <types.Types[types.TUINT8]> bool))))
  2391  // if !b { x ^= c } => x ^= !b * c
  2392  (CondSelect x op:(Xor8 <t> x c:(Const8)) bool) &&
  2393  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2394  	(Xor8 x (Mul8 <t> c (CvtBoolToUint8 <t> (Not <bool.Type> bool))))
  2395  (CondSelect x op:(Xor(64|32|16) <t> x c:(Const(64|32|16))) bool) &&
  2396  	rewriteCondSelectIntoMath(config, op.Op, c.AuxInt) =>
  2397  	(Xor(64|32|16) x (Mul(64|32|16) <t> c (ZeroExt8to(64|32|16) <t> (CvtBoolToUint8 <types.Types[types.TUINT8]> (Not <bool.Type> bool)))))
  2398  
  2399  // bool(int(x)) => x
  2400  (Neq8                                (CvtBoolToUint8 x)  (Const8          [0])) => x
  2401  (Neq8                                (CvtBoolToUint8 x)  (Const8          [1])) => (Not x)
  2402  (Eq8                                 (CvtBoolToUint8 x)  (Const8          [1])) => x
  2403  (Eq8                                 (CvtBoolToUint8 x)  (Const8          [0])) => (Not x)
  2404  (Neq(64|32|16) (ZeroExt8to(64|32|16) (CvtBoolToUint8 x)) (Const(64|32|16) [0])) => x
  2405  (Neq(64|32|16) (ZeroExt8to(64|32|16) (CvtBoolToUint8 x)) (Const(64|32|16) [1])) => (Not x)
  2406  (Eq(64|32|16)  (ZeroExt8to(64|32|16) (CvtBoolToUint8 x)) (Const(64|32|16) [1])) => x
  2407  (Eq(64|32|16)  (ZeroExt8to(64|32|16) (CvtBoolToUint8 x)) (Const(64|32|16) [0])) => (Not x)
  2408  
  2409  // Canonicalize sext(int(bool)) => zext(int(bool))
  2410  (SignExt8to(64|32|16) cvt:(CvtBoolToUint8 bool)) => (ZeroExt8to(64|32|16) cvt)
  2411  

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